Getting Your Emails to the Inbox: The Complete Guide to Email Deliverability in 2024

Does your email marketing seem to end up in subscribers’ spam folders or get lost in transit more often than you’d like? Maximizing email deliverability to reach inboxes takes work. Learn strategies to improve your email delivery rates with this comprehensive guide.

Page Contents

What is Email Deliverability?

When sending emails to a list of subscribers or customers, marketers often focus solely on the total number of emails successfully delivered. But there’s an important distinction between email delivery and email deliverability that can dramatically impact the success of email marketing campaigns.

Email delivery simply refers to whether an email was technically sent and accepted by the receiving email server. As long as no hard errors occur like invalid addresses causing bounces, the email is considered successfully delivered.

However, just because an email is delivered does not guarantee it will be seen and read by the recipient. This is where email deliverability comes in.

Email Deliverability Definition

Email deliverability refers specifically to whether a delivered email ends up in the primary inbox of the recipient. If an email is sent and accepted by the mail server but filtered into the ‘Promotions’, ‘Spam’, or ‘Social’ tabs, it is still considered delivered but has poor inbox deliverability.

The goal of maximizing email deliverability is to ensure emails avoid spam filters and reach subscribers’ main inboxes where they are most likely to be opened and read.

Why Does Inbox Placement Matter?

If an email campaign is delivered to 1,000 subscribers but only lands in 200 inboxes while the other 800 are filtered into other tabs or spam, the effectiveness of that campaign is diminished.

  • Opens and clicks decrease: Emails in the primary inbox see significantly higher open and click-through rates compared to other tabs. Emails in the spam folder are essentially invisible.
  • Engagement drops: Recipients are less likely to thoroughly read, share, or otherwise engage with emails that are filtered into secondary tabs.
  • Future emails affected: Low inbox placement signals to mail providers that future emails are less desired, exacerbating the problem.

Essentially, maximizing email deliverability leads to better campaign performance. But how exactly is inbox placement determined in the first place?

How Email Providers Determine Inbox Placement

Email service providers like Gmail and Outlook use complex algorithms and machine learning to analyze each incoming email and decide whether it should go to the primary inbox or not.

Some key signals used in inbox placement decisions:

  • Sender reputation – Past sending behavior and complaint rates
  • Authentication – Use of SPF, DKIM, DMARC to confirm source
  • EngagementOpen and click rates on past emails from sender
  • ContentSpam trigger words, formatting, images, links etc.

Marketers have limited visibility into these tab placement algorithms. But by optimizing key factors like reputation, engagement and content over time, inbox placement can be improved.

Email Deliverability vs Delivery Rates

When analyzing the performance of an email campaign, deliverability and delivery rates are two related but distinct metrics:

  • Delivery rate measures the percentage of total emails sent that were accepted by the receiver’s email server, regardless of tab placement. This indicates technical errors like bounced emails.
  • Deliverability rate measures the percentage of total emails sent that reached recipients’ primary inboxes. This indicates whether campaigns are being filtered by spam algorithms.

For example, if 100 emails are sent in a campaign and 90 are delivered but only 50 reach inboxes, then:

  • Delivery rate = 90%
  • Deliverability rate = 50%

Ideally, both delivery and deliverability rates should be maximized for email marketing success. But focusing solely on delivery overlooks the crucial inbox placement element. Checking deliverability reveals whether further optimization is needed or not.

Takeaways on Email Deliverability

  • It refers specifically to emails landing in the primary inbox vs other tabs or spam.
  • Maximizing inbox placement is key for open rates, engagement, and future send reputation.
  • Factors like reputation, authentication, and content affect algorithmic tab placement decisions.
  • Delivery vs deliverability provide related but different insights on campaign performance.

Getting a handle on principles of email deliverability provides a better understanding of the complex journey an email takes before reaching subscribers, and equips marketers with the knowledge to improve email performance.

Why Does Email Deliverability Matter for Email Marketing?

Getting an email marketing campaign delivered is only the first step. Having it actually reach subscribers’ inboxes is just as crucial. Maximizing email deliverability is key to the success of any email marketing effort.

There are two main reasons why focusing on deliverability should be a priority:

1. Deliverability Helps Increase Conversions

The end goal of email marketing is ultimately to drive some type of conversion – whether that’s a sale, signup, content download, event registration etc.

Landing in the primary inbox is the best way to enable those conversions.

When an email ends up in the ‘Promotions’ tab, subscribers may never see it. If filtered to spam, it’s essentially lost. Even the ‘Social’ tab sees significantly lower engagement levels.

But the primary inbox is front and center. Subscribers expect important and relevant emails to appear there.

High Deliverability Boosts Open and Click-Through Rates

Studies show that emails reaching the primary inbox enjoy much higher open and click-through rates. Some key stats:

With higher visibility and engagement, subscribers are more likely to take the desired action like making a purchase.

More Opens and Clicks Signal Relevance

Higher open and click rates communicate relevance to email providers. Algorithms will be more likely to keep that sender’s future emails in the inbox. This creates a positive deliverability cycle benefitting future conversion rates as well.

On the other hand, low engagement due to poor deliverability signals that future emails should be filtered lower. This vicious cycle spirals into continually worse inbox placement and fewer conversions.

Tailored Content Performs Better

Proper inbox placement allows marketers to get more creative and optimize campaigns to drive specific actions. For example, sending targeted content with customized subject lines based on interests and behaviors.

Whereas emails in other tabs require broader mass appeal and generic subjects just to get a chance at being opened. The result is lower conversions.

In summary, achieving high email deliverability is crucial for enabling better engagement, continual inbox placement, and ultimately higher conversion rates from email campaigns.

2. Deliverability Helps Avoid Being Labeled a Spammer

The second reason deliverability matters is that low rates can potentially lead to being outright blocked and labeled a spammer.

Internet service providers have strict policies in place to protect customers from unwanted email. If a sender shows patterns of low engagement and poor deliverability, they run the risk of temporary or even permanent blacklisting.

Some ways low deliverability can cause spammer labeling:

Low Open and Click Rates Signal Irrelevance

As mentioned above, when emails consistently have poor open and click-through rates, it suggests recipients don’t find them useful. Continually sending irrelevant content despite low engagement is akin to spam behavior.

After enough negative signals, providers may preemptively filter future emails to protect subscribers from disruptive experiences.

High Unsubscribe and Complaint Rates

Similarly, if high percentages of recipients are unsubscribing or reporting emails as spam, it indicates frustration with the sender. Too many complaints can trigger blocking.

Well-designed emails that account for subscribers’ preferences should not see mass unsubscribes. So high rates again signal possible spam activity.

Sudden Volume Spikes Look Like Spam Attacks

If a sender instantly sends huge volumes of emails, perhaps from purchasing lists, providers can interpret this as a spam attack. Gradual volume ramp-ups are safer.

Sudden spikes often mean the sender hasn’t earned the trust and reputation required for larger mailing lists. So providers block them to prevent potential spam from reaching new recipients.

Authentication Issues Imply Forged Emails

Proper email authentication with protocols like SPF, DKIM, and DMARC confirms a message’s origin. But missing or invalid authentication can cause emails to be distrusted and blocked as possible phishing scams or other spam tactics.

While being labeled a spammer is an extreme outcome, the underlying patterns that trigger it – low engagement, improper practices, strange sending volumes – also directly cause deliverability issues. So addressing the root problems solves both.

Takeaways on the Importance of Deliverability

Maintaining high email deliverability should be a priority for any email marketer. It:

  • Helps increase conversions by improving visibility, engagament and relevance.
  • Avoids detrimental spam labeling by staying aligned with best practices for reputation and trust.

By keeping deliverability top of mind and optimizing campaigns appropriately, marketers give themselves the best chance of email success. Monitoring key metrics and being proactive allows catching issues early before they spiral. A focus on inbox placement provides the foundation for impactful email marketing.

What is Considered a Good Email Deliverability Rate?

Given how crucial maximizing inbox placement is for email success, an important question arises – what target deliverability rate should marketers aim for? With many factors in play, there is no single perfection number. However, some best practices and industry averages provide a good framework.

General Email Deliverability Benchmarks

Experts agree that a rate of 95% or higher is considered an excellent email deliverability benchmark across most industries. At 95% or above, the vast majority of sent emails are reaching subscriber inboxes as intended to be opened and engaged with.

That said, a deliverability rate as low as 90% could still be acceptable depending on circumstances. Anything below 85%, however, starts to signal issues with reputation, authentication, content or other factors dragging down inbox placement.

Deliverability can fluctuate slightly from month to month, but in general, the higher the better. Monitoring trends is key – a rate steadily declining over time indicates problems. Sudden one-time drops also warrant investigation.

Factors That Impact Acceptable Deliverability Rates

While 95%+ is a solid target, the deliverability rate considered ‘good’ for a particular sender can vary based on several factors:

Industry Benchmarks

  • Some industries like insurance and real estate see higher average deliverability vs. retail and entertainment. Evaluating your rate vs competitors provides context.

Email Type

  • Marketing emails may have more fluctuation than strictly transactional emails related to purchases and account management.

List Quality

  • An older, outdated list will make 95%+ harder to achieve than a newly opted-in list. Quality impacts potential.

Historical Reputation

  • Senders with long history and reputation have more leeway than a brand new sender.

Sending Volume

  • Large, established brands sending millions have tighter margins. Newer senders with smaller lists can more easily stay at 95%+.

Email Purpose

  • A one-off promotional email may be held to a higher deliverability bar than a repeating newsletter subscribers expect.

While 95% is the general recommendation, the expected range for acceptable deliverability rates factors in list size, industry, history, email purpose and other attributes. Monitoring trends is key.

Average Marketing Email Deliverability Rates

Marketing emails are proactive communications intended to drive interest or sales, like promotions, newsletters, and drip campaigns. Industry benchmarks help provide context on real-world deliverability.

According to SparkPost data, average marketing email deliverability rates across all industries tend to fall around 92-93% on average.

Some variance exists between categories:

  • Retail marketing emails see avg rates around 90-92%
  • Finance and insurance avg closer to 95%
  • Non-profits at 93-94%
  • Technology and telecom around 94-95%

Rates also tend to trend a few points lower on Mondays and Tuesdays when overall email volume is higher, compared to late week.

In general, marketing deliverability in the low 90% range is common but still leaves room for optimization to reach the desired 95%+ target. Reviewing volume, lists, and engagement metrics can reveal opportunities.

Average Transactional Email Deliverability Rates

Transactional or operational emails serve purely utility purposes like purchase receipts, password resets, or shipping confirmations.

Deliverability rates for transactional messages tend to exceed those of marketing emails:

  • 95-97% deliverability is common for transactional messages.
  • Finance and e-commerce transactional reach as high as 98%.
  • Transactional emails also have less day-to-day fluctuation.

The higher priority of transactional content focused on user needs means providers are more inclined to place them directly in inboxes. Deliverability issues are also quickly noticed and complained about since they directly impact customers.

Achieving the 95% inbox placement goal is easier for transactional email, but still not guaranteed. Continually authenticating messages and maintaining a great user experience is important.

Takeaways for Determining a ‘Good’ Deliverability Rate

  • While 95% is a solid overall target, acceptable rates depend on context like industry, list quality, and email purpose.
  • On average, marketing emails see deliverability around 92-93% and transactional emails 95-97%.
  • Gap between current and target rate reveals opportunities to optimize reputation, engagement, and other factors.
  • Rates below 85% signal more urgent problems affecting email placement.

Given the many intersecting factors, determining a good benchmark requires both researching industry averages and assessing circumstances. The context will dictate reasonable expectations. But ultimately, achieving 95% inbox placement or better enables the highest email marketing results.

How to Calculate Your Email Deliverability Rate

Understanding email deliverability benchmarks is useful, but marketers also need to know how to calculate their own campaign’s current deliverability rate for comparison. This requires analyzing delivery metrics to quantify the percentage of emails reaching the inbox.

Additionally, diving into bounce rates provides insight on technical issues impacting the calculation. Hard bounces should be excluded from the deliverability rate, while soft bounces offer clues for optimization.

The Formula for Calculating Deliverability Rate

The email deliverability rate formula is straightforward:

Deliverability Rate = (Number of Emails Delivered to Inbox / Total Emails Sent) x 100

The key pieces of data needed are:

Plugging those into the formula provides the inbox placement percentage, which can then be compared to industry benchmarks.

Here is an example calculation:

  • 1,000 email campaign sent
  • 950 successfully reached inboxes
  • Deliverability rate = (950 / 1,000) x 100 = 95%

This imaginary campaign meets the general 95% target. But the calculation is the first step to isolating issues dragging down the rate.

Hard Bounces vs Soft Bounces

A “bounce” occurs when an email is rejected by the receiving server and fails to reach the subscriber’s inbox. But bounces are not all created equal. Analyzing bounce types provides deliverability insights.

Hard Bounce

A hard bounce means the email address is permanently invalid and does not exist – essentially a dead lead. Common causes are typos, closed accounts and churned users.

Hard bounces should be excluded from the deliverability rate calculation. They represent bad data rather than issues with inbox placement. Deduplicating the recipient list to omit hard bounces provides a more accurate deliverability benchmark.

Too many hard bounces indicate poor list quality. Cleaning up lists by removing invalid emails improves both overall delivery and targetable reach.

Soft Bounce

A soft bounce is a temporary delivery failure due to factors like:

  • Full inbox preventing message receipt
  • Server downtime
  • Email labeled as spam
  • Message too large

Soft bounces mean the address is still valid despite the temporary failure. These should be included in the deliverability rate denominator since the subscriber would have received the message given ideal circumstances.

Trends in soft bounces reveal opportunities to improve deliverability. For example:

  • High spam bounces may indicate issues with authentication or content formatting.
  • Size limits could mean paring down design elements for smoother inbox delivery.

Ideally the soft bounce rate should be kept below 3%. Any higher merits a deeper look at the specific types of bounces to identify areas of focus.

Takeaways on Calculating Deliverability

To summarize best practices on measuring email deliverability:

  • Use a simple formula of emails delivered to the inbox divided by total emails sent.
  • Exclude hard bounces from the calculation to avoid skewing the rate.
  • Include soft bounces to account for temporary issues solvable through optimization.
  • Analyze bounce types for additional insights into blocks on delivery.

Regularly calculating deliverability rates, benchmarking against industry averages, and drilling into bounce data empowers marketers to continually improve performance and keep their emails out of spam traps and in subscribers’ inboxes where they belong.

How to Test and Track Your Email Deliverability

Calculating a deliverability rate is a good first step. But marketers need ways to test how future emails may fare before sending them, while also continually monitoring performance over time.

Thankfully, a range of deliverability testing and tracking tools exist to provide visibility into inbox placement trends and identify issues to resolve:

Pre-Send Email Deliverability Testing

Before hitting send on a large campaign, it’s prudent to test and confirm the email is primed for inbox delivery with a few options:

Built-In Spam Testing

Many email service providers like Mailchimp and Omnisend have proprietary spam testing tools that can analyze a message and provide a preview spam score. High-risk content like spam trigger words can be modified to improve the score before sending.

Spam Filter Testing Services

Third-party services like Litmus Spam Testing run emails through real spam filters and inbox placement algorithms. They provide granular reports detailing any red flags that could redirect emails to spam or promotions. Addressing identified issues boosts deliverability.

Seed Groups

Send a test email to a small group of target recipients or internal team members to confirm inbox placement before the main send. Slow rollout mitigates impact if the test underperforms. Seed groups help catch major issues with authentication or bad sender reputation.

Spam Reference Sites

Copy and paste email content into tools like to detect any obvious yellow flags. While not foolproof, they catch easy-to-fix formatting problems and risky phrases. Quickly optimizing these improves deliverability odds.

Testing upfront helps steer clear of catastrophic spam misclassification while also maximizing inbox placement. But ongoing tracking is equally important.

Monitoring and Tracking Deliverability Over Time

After a campaign is sent, marketers need to continually track metrics that indicate deliverability health. Here are key indicators to follow:

Overall Deliverability Rate

As discussed previously, regularly calculating the inbox rate relative to sends monitors the big picture. Rate declining? Time to investigate why.

Bounce Rates

Segmenting bounces into hard vs soft categories reveals list quality issues causing permanent failures vs temporary setbacks.

Aim to keep hard bounces under 2% and soft bounces under 5%. Trends exceeding those suggest problems.

Engagement Rates

Are open, click-through, and unsubscribe rates declining? Low engagement directly hurts inbox placement over time. An engagement scoring model helps identify poor performers.

Complaint Rates

How frequently are spam complaints coming in? Frequent user frustration should be addressed – improving content and targeting avoids further damage.

Blacklist Checks

Services like MXToolbox can confirm if any sending IP addresses have ended up on spam blacklists. Being blacklisted severely restricts email delivery and must be fixed immediately.

Tracking performance along these deliverability dimensions spotlights any creeping issues before they transform into catastrophes deserving of spam folder purgatory.

Takeaways on Testing and Tracking Deliverability

Vigilantly monitoring email deliverability performance provides the data needed to make smart optimizations like:

  • Improving subject lines and content formatting
  • Removing inactive subscribers
  • Correcting authentication issues
  • Gradually ramping up volume

And services like spam testing and blacklist monitoring help avoid disastrous mistakes when preparing and sending campaigns.

A proactive approach combining testing, tracking, and optimization sustains long-term deliverability success. Don’t leave it up to chance – implement the tools and processes to take control of inbox placement.

Factors That Impact Your Email Deliverability Rates

Achieving a high deliverability rate requires optimizing several interconnected factors. Issues with any one area often influence and exacerbate problems with others.

Understanding the main components impacting inbox placement enables marketers to catch problems early and troubleshoot more effectively.

Reputation of Your Domain and IP Address

The reputation attached to a sender’s domain and IP address is a primary factor determining inbox placement. Both contribute to an overall “sender score.”

Higher reputation means emails are trusted to land in the inbox. Lower reputation leads to extra spam filtering scrutiny.

How Domain and IP Reputations Are Calculated

There is no single formula. But key signals used by major email providers include:

Domain Reputation Factors:

  • Complaint rates – Spam button clicks or abuse reports
  • Bounce rates – High hard bounces indicate low quality
  • Engagement metrics – Low opens and clicks signal irrelevant content
  • Spam traps – Sending to fake addresses implies purchased lists

IP Reputation Factors:

  • History of security issues like malware or hacking originating from the IP
  • Previous sender behavior and traffic from the IP – spam or phishing
  • Consistency of location and volume – strange patterns cause distrust

Based on these types of signals, every domain and IP address earn a reputation score. Higher scores lead to better inbox placement.

Building a Good Email Sending Reputation

With reputation playing such a pivotal role, senders should be proactive about cultivating it through best practices like:

  • Warming up new IPs gradually – Sudden spikes look suspicious
  • Carefully managing subscriber lists – Follow opt-in laws, prune inactives, avoid purchasing lists
  • Ensuring proper authentication – Use SPF, DKIM, and DMARC
  • Sending consistently valuable content – Interesting subject lines, engaging content, valuable offers
  • Monitoring metrics for issues – Low engagement, increasing complaints, etc.
  • Checking blacklist status – Avoid any listings to remain trustworthy

Being patient and following deliverability best practices establishes strong domain and IP reputations over time. This benefits inbox placement and protects against sudden drops.

Proper Email Authentication

As mentioned, authenticating an email’s origin is vital for deliverability. SPF, DKIM, and DMARC should be implemented to maximize inbox placement.

SPF Verifies Sending Domains

When emails arrive from those two sources, SPF validates the domain matches and facilitates delivery. Emails from other servers would fail SPF checks and risk going to spam.

DKIM Checks Email Integrity

DKIM digitally signs each individual email to certify the content has not been tampered with in transit. The signature ties the message securely back to the authorized sending domain.

The signature is created using a private key only the sender possesses. Receiving servers verify it against the published public key to confirm integrity. Valid DKIM signals legitimate emails.


DMARC adds a final layer of protection, reconciling results from SPF and DKIM checks. If both align and authenticate, DMARC instructs receivers to deliver to the inbox. Mismatches may end up in spam or rejected entirely.

Properly implementing this authentication trio reassures ISPs that emails genuinely originate from approved domains and servers. This facilitates inbox placement.

Quality of Your Email Lists and Engagement

Even with pristine reputation and authentication, poor list quality and engagement can undermine deliverability.

Keep Lists Fresh and Clean

Diligent list management is essential for limiting bounces and complaints. Best practices include:

  • Prune inactives – Remove non-openers after extended periods to avoid building up spam traps
  • Remove hard bounces – Deactivate invalid email addresses causing bounces
  • Only add opted-in contacts – Never purchase or rent lists which often include spam traps
  • Segment strategically – Group engaged subscribers separately from cold prospects

Keeping lists focused on truly active subscribers boosts positive engagement metrics that support deliverability.

Monitor Engagement Trends

Beyond list quality itself, ISPs scrutinize recipient behavior in reaction to emails.

Low open and click rates signal recipients find the content irrelevant. Mass deletions and spam complaints indicate frustration.

If engagement drops significantly, inbox placement will follow suit over time as algorithms deduce subscribers don’t value the emails.

Proactively monitoring key metrics helps surface list and targeting issues early on before they manifest in falling deliverability.

Infrastructure for Sending Bulk Emails

The technology used to dispatch emails also influences inbox placement outcomes. Shared IPs are common but come with deliverability considerations.

Shared IP Addresses

Many email providers use shared IP pools that rotate sending IPs across all customers to manage deliverability. The benefit is tapping the provider’s established reputation.

The drawback is reduced control – other senders’ mistakes can tarnish IP reputation. There is also potential for reaching volume limits on shared resources.

Shared IPs work for most use cases but leave marketers dependent on the provider’s deliverability management.

Dedicated IP Addresses

Larger senders may invest in dedicated IPs exclusively assigned to their brand. This offers more autonomy to cultivate reputation and limits sharing degradation from others.

But dedicated IPs also require more hands-on management. Marketers must be meticulous when warming up IP volume and adhering to best practices – any missteps fall solely on them.

The infrastructure choice aligns with the brand’s size, volume, and technical capabilities. But regardless of approach, proper management and monitoring help maximize placement.

Strength of Your Email Copy and Content

Even with all the technical factors covered, if an email’s content misses the mark, inbox placement will ultimately suffer.

Ensure Subject Lines Are Relevant

The subject line is the first touchpoint with subscribers – it must clearly reflect the value inside and align with their interests.

Otherwise, the risk is recipients assuming the message is unimportant and either ignoring it or marking it as irrelevant spam. Subject lines set the engagement tone.

Write Valuable Email Copy

What good is the cleverest subject line if the email copy itself disappoints? Body content must deliver on the subject’s promise with useful information subscribers find worth their time.

Well-written and on-target copy keeps recipients happy, engaged, and forthcoming with their mailbox real estate. Give them a reason to care.

Design and Format for Deliverability

Proper formatting and design ensure emails render well on mobile devices and avoid quirks that might trigger spam filters. Consider:

  • Use a responsive template with simple image blocking
  • Avoid large files or bandwidth-heavy elements
  • Stick to common, safe fonts and easy-to-read typography
  • Make unsubscribe and company information readily accessible

Technical finesse creates a transparent reading experience focused solely on an email’s value.

Takeaways on Factors Impacting Deliverability

Maintaining strong inbox placement requires vigilance across multiple factors:

  • Earning positive domain and IP reputations
  • Using proper authentication protocols
  • Cultivating engaged, healthy subscriber lists
  • Choosing email infrastructure tailored to needs
  • Crafting compelling content worth reading

Regularly examining each area reveals opportunities to refine tactics and strategy. An email’s inbox fate rests in getting the details right.

How to Improve Your Email Deliverability Rates

Despite best efforts, there may be times when deliverability rates still struggle to find their footing. Rather than accept spam folder-bound fate, marketers have options to diagnose issues and get their emails back on track.

Here are key steps to take in order to improve deliverability rates when they start slipping:

Confirm Deliverability Baselines

Before taking action, reconfirm current deliverability rates and benchmarks. Calculate the latest rate based on recent sends to see current inbox placement performance.

Review historical trends to detect any significant changes or sudden drops that triggered concern.

Compare your rate to industry averages and top competitors to gauge how far off the pace it may be.

With fresh baselines established, apply strategies to get deliverability back on target.

Warm Up New Domains and IPs Slowly

If starting fresh with a new sending domain or dedicated IP address, take time to gradually warm it up.

Sudden large email volumes from a new domain/IP with no history will often get spam-trapped. Building volume slowly establishes positive activity patterns and avoids alerting filters.

Follow a Ramp-Up Schedule

When warming a new IP, scale message volume in measured phases, tracking deliverability at each stage:

  • First 3 days: Send to only 1-5% of list (engaged subscribers). Send 50-100 emails total.
  • First 10 days: Increase to 10-15% of list. Send 500-1,000 emails total.
  • First 30 days: Scale up to 25-50% of list. Send 2,500-5,000 emails total.

Adjust schedule based on resulting deliverability rates. If meeting targets, continue ramping up. If rates drop, pause and address potential issues before resuming at that volume.

Begin with Engaged Subscribers

When starting to build reputation for new domains/IPs, only send to the most loyal and engaged existing subscribers at first.

Highly engaged users are most likely to open and click on early emails, keeping your relevant signal strong out of the gates. Initial positive signs facilitate quicker trust gains for new senders.

Proceed cautiously, and new assets can establish strong deliverability in the critical early tenure window.

Improve Low Subscriber Engagement

Beyond new assets, low open and click rates can also indicate content problems diminishing deliverability for established domains.

Reinvigorate subscribers with re-engagement campaigns:

Send Relevant Content

Analyze past high-performing email topics and successful landing pages. Build a campaign showcasing fresh content aligned with those interests.

Promote Popular Products

Highlight top-selling items or recently viewed products subscribers already demonstrated an affinity for.

Use Behavioral Triggers

Send emails when specific actions occur, like replenishing shopping cart items that were abandoned. Contextual relevance boosts open potential.

Make Content More Interactive

Inject interactive elements like polls and surveys to involve recipients and get them re-engaged.

Any tactics to get proven buyer segments re-engaged will in turn improve deliverability by signaling renewed subscriber interest.

Optimize Your Email Copy and Content

Beyond overall engagement, fine-tuning email content itself can lift lackluster open and click rates.

Personalize Copy to Recipients

Personalized subject lines, offers and copy tailored to recipients’ interests/history get higher open rates. Even minimal merges of first names grab attention.

Refresh Stale Content

Swap out any dated information, outdated offers and stale content that does not compel action.

Enhance Subject Lines

Rewrite ambiguous or overused subject lines that blend into the inbox. Test specific, curiosity-sparking subjects.

Prominently Place CTAs

Ensure clear call-to-action buttons flow logically within the email content and are visually emphasized.

Preview Text Across Devices

Ensure the preview text displayed in inboxes accurately conveys key context and persuades opening.

Minor copy tweaks and content refreshers refocus emails on value to recipients.

Re-Confirm Proper Authentication

Authentication issues severely impact deliverability. Verify SPF, DKIM and DMARC records are all implemented and properly configured for sending domains.

Audit SPF Records

Confirm SPF records designate all current legitimate sending servers. Any infrastructure changes without SPF updates cause authentication failures.

Check DKIM Signatures

Ensure the DKIM public key is still referenced by receiving servers. Change in hosting can cause signature breaks without key updates.

Review DMARC Alignments

If SPF and DKIM records point to different or invalid locations, DMARC alignment fails. Tighten integration.

Occasionally re-checking and updating authentication settings ensures consistent inbox placement.

Monitor and Manage Blacklist Status

If previous emails were flagged as spam, sending infrastructure may have ended up on spam blacklists – severely restricting future delivery.

Check Blacklist Status

Use tools like MXToolbox and IsNotSpam to confirm if IP addresses are blacklisted.

Request Blacklist Removal

If found on any blacklists, submit de-listing requests immediately emphasizing any fixes and improvements made. Continued blacklisting drastically damages deliverability.

Examine Why Listing Occurred

If listed, the specific reason will usually be cited, like spam complaints or suspicious traffic. Address the root cause to avoid repeat issues.

Remove Inactive Subscribers

Unengaged subscribers with months of email inactivity degrade sender reputation and deliverability over time by remaining available to be flagged as spam traps.

Segment Subscribers

Divide lists into active subscribers opening/clicking within the past 3 months vs. inactive members with no engagement.

Remove Long-Term Inactives

Delete subscribers inactive for 6 months or more to improve overall list quality and open rates. But first…

Attempt Re-Engagement

Before deleting inactives altogether, make re-engagement attempts through campaigns promoting popular/recent products. This gives them a chance to re-engage before removal.

Pruning unengaged subscribers who have grown stale refocuses delivery on validated interested parties.

Gain Opt-In Consent From All Subscribers

Purchased or rented lists often contain spam traps and bring unmotivated contacts hurting engagement metrics. Refocus on opted-in members.

Scrub Any Purchased Lists

Review subscriber sources and remove any batch imports purchased through brokers or in bulk without individual consent.

Implement Double Opt-In

Install a double opt-in that requires confirming subscriptions via email to validate genuine interest. This filters out non-committed contacts upfront.

Monitor Subscription Sources

Analyze top subscription sources to identify any providing low-quality additions with poor conversion potential. Refine targeting.

Renewed focus on active, engaged and consenting subscribers results in a list primed for inbox placement.

Takeaways for Improving Low Deliverability

With a deliverability rate below ideal benchmarks, marketers can follow these troubleshooting steps:

  • Confirm current rate and changes using analytics
  • Warm up any new domains/IPs gradually
  • Improve subscriber engagement with targeted campaigns
  • Optimize email copy and content to drive opens
  • Re-check SPF, DKIM and DMARC authentication records
  • Monitor blacklist status and request removal if needed
  • Prune inactive subscribers to focus on engaged
  • Ensure all subscribers are double opted-in

Executing testing and improvements across these areas will provide the foundational inbox placement boost needed to get deliverability back on track.

Email Deliverability Tools and Services

While optimizing campaigns and infrastructure is crucial, leveraging the right tools and services facilitates monitoring deliverability and identifying opportunities.

Here are some top options across key categories:

Email Warmup Tools

Warming up IP addresses and domains safely requires taking it slow. Warmup tools enable gradually increasing volume while tracking placement.


Mystrika offers advanced options for warming up IPs through its platform. Features include:

  • Automated ramp-up scheduling with volume recommendations
  • Detailed warmup and placement analytics
  • Pool of pre-warmed seed accounts to send initial emails
  • Options to target warm up emails geographically

SendGrid IP Warm Up

SendGrid’s built-in warmup functionality lets users gradually scale up IPs following recommended volumes and monitoring performance.

Mailjet IP Warm Up

Mailjet also provides IP warmup capabilities and deliverability performance tracking to transition new IPs safely.

250ok IP Warm Up

250ok offers advanced IP warmup supplemented by dedicated deliverability consultation and ongoing performance optimization.

Email Deliverability Monitoring Tools

Ongoing monitoring and testing helps nip deliverability drops in the bud before they spiral.

Litmus Spam Testing

Litmus Spam Testing provides predictive spam scores highlighting potential inbox placement issues. Immediate visibility allows optimizing emails pre-send.

SendGrid Deliverability Dashboard

The SendGrid dashboard tracks key metrics like spam rate, delivery rate, invalid emails, bounces, and more for monitoring purposes.

Mailgun Deliverability Tests

Mailgun deliverability tools run emails through spam filters and blacklist databases to identify problems impacting placement.

SparkPost Signals

Signals uses big data across 4 trillion emails to benchmark performance and provide predictive insights on optimizing future deliverability.

Email Analytics Tools

Analytics revealing big picture subscriber engagement trends inform effective optimization tactics.


Omnisend provides in-depth analytics on opens, clicks, bounce rates, and unsubscribes segmented across campaigns.

Mailchimp Reports

Mailchimp’s built-in reporting and insights provide engagement data for assessing content performance.


Drip’s analytics focus on subscriber behavioral trends to help marketers identify high-value engagement opportunities through lifecycle.

Custom dashboards analyze performance across multiple subscription funnels using engagement-focused metrics and cohort trends.

Takeaways on Deliverability Tools

The right tools provide visibility into how campaigns are performing under the hood and where opportunities exist, arming marketers with actionable data to drive optimization.

Consider signup and engagement tracking, predictive spam testing, and warmup services as some of the most effective solutions to get tangible lifts in inbox placement.

An environment promoting constant small improvements is the path to sustaining long-term deliverability success.

Key Takeaways and Next Steps

Maximizing email deliverability requires vigilance across many interconnected factors. For marketers seeking to improve their inbox placement, here are the key takeaways to remember:

Summary of Main Points

  • Deliverability specifically measures inbox placement, not just general delivery. Landing in primary inboxes boosts engagement and conversions.
  • Aim for 95%+ deliverability as a strong benchmark to strive for, but review contextual factors like list size and industry.
  • Monitor bounced emails since hard bounces indicate list quality issues and soft bounces reveal technical opportunities.
  • Reputation is built over time by sending valuable content subscribers want, avoiding spam triggers, and cultivating engagement.
  • Proper authentication is crucial to confirm emails as legitimate – use SPF, DKIM, and DMARC.
  • List quality and subscriber engagement heavily influence long-term deliverability through behavior signals to ISPs.
  • Email copy and content must be relevant and compelling to motivate subscriber action.
  • Tools for testing and monitoring provide the visibility needed to catch issues proactively.
  • Ongoing optimizations and vigilance are required to sustain strong inbox placement.

The complexity of email deliverability may seem daunting. But breaking down key elements into manageable focus areas simplifies the process.

Where to Focus First if Deliverability is Low

For marketers seeking to get seemingly derailed deliverability back on track, a few high-impact areas to focus on first:

Review Authentication and Infrastructure

  • Ensure SPF, DKIM, and DMARC are properly set up for sending domains.
  • Check that any infrastructure changes didn’t invalidate authentications.
  • Audit IP addresses for blacklisting issues.

Analyze Bounce Rates and List Quality

  • Profile subscribers to identify any high-risk segments with low engagement skewing reputation.
  • Remove hard bounces and prune long-inactive subscribers.
  • Review subscription sources for low-quality additions.

Test Messages with Spam Tools Pre-Send

  • Leverage spam testing before campaigns to catch issues proactively.
  • Refine messages until spam potential is low before main send.

Assess Audience Alignment

  • Gauge whether content truly resonates with subscriber interests.
  • Evaluate performance of subject lines and calls to action.
  • Confirm subscription preferences and consents are up to date.

With focus on quick-win areas like authentication, list quality, pre-send testing, and audience alignment, marketers can regain momentum on delivering emails to inboxes.

Final Thoughts

Email deliverability will always require ongoing optimization, learning, and vigilance. But rests in mastering the fundamentals.

Armed with an understanding of key factors like reputation, engagement, and infrastructure, marketers can take control of their inbox placement fate. Small but consistent gains compound.

Rather than view deliverability as an opaque algorithmic black box, leverage available tools and strategies to illuminate the path to higher rates. Commitment to improvement delivers results.

Key Takeaways on Email Deliverability Rates

Getting emails successfully delivered to recipients’ inboxes requires coordination across many factors. Here are the core takeaways on maximizing email deliverability:

  • Deliverability refers specifically to inbox placement, not just general delivery. The inbox is the most critical destination for engagement.
  • A 95%+ deliverability rate is a benchmark to aim for, but the acceptable range depends on context like list size and industry.
  • Regularly calculate your rate using emails delivered to the inbox divided by total emails sent. Exclude hard bounces.
  • Domain and IP reputations heavily influence inbox placement based on past behavior like complaints and spam triggers.
  • Proper authentication with SPF, DKIM and DMARC confirms emails are legitimate and facilitates delivery.
  • Focus on engaged, high-quality subscriber lists. Prune inactives and avoid purchased lists.
  • Monitor engagement metrics like open and click-through rates which directly impact future inbox placement.
  • The right email copy and content boosts opens. Refresh stale messaging and promote relevance.
  • Warm up new IP addresses gradually to build trust and avoid sudden spikes that appear like spam.
  • Pre-send spam testing identifies issues to optimize before mailing to prevent blacklists.
  • Continual small optimizations compound over time into improved email deliverability. Monitor rates and trends closely.

With a comprehensive understanding of the key principles and components impacting inbox placement, marketers can make steady progress towards maximizing email deliverability. Minor improvements add up to major results.

Frequently Asked Questions About Email Deliverability

What is a good email deliverability rate?

Aim for 95% or higher as a good benchmark deliverability rate. 85% or lower indicates issues needing improvement. Target rate depends on factors like industry, email type and list size.

How is deliverability rate calculated?

Deliverability rate = (Emails to Inbox / Total Emails Sent) x 100. Remove hard bounces from the numerator to avoid skewing the rate down.

What affects email sender reputation?

Sender reputation is determined by factors like complaint rates, spam triggers, engagement metrics, bounce rates, and proper authentication. It directly impacts deliverability.

How can I check if my IP is blacklisted?

Use blacklist checking tools like MXToolbox or IsNotSpam to search major spam databases and see if your IP address has been added to any blacklists.

Why is email authentication important?

Proper SPF, DKIM and DMARC authentication confirms to ISPs that emails genuinely come from authorized servers and helps facilitate inbox placement.

Should I warm up new IP addresses?

Yes, gradually warm up any new IPs by steadily increasing sending volume over time. Sudden large volumes from a new IP may be seen as a spam attack.

How can I improve low engagement and open rates?

Refresh content, increase personalization, target highly engaged segments, and test new subject lines to re-engage subscribers with relevant content.