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Postmark deliverability: Why it's low & not working?

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    Ensuring that your emails really land in inboxes is absolutely vital in the fast-paced realm of digital communication. This is where Postmark’s email deliverability capabilities help. Postmark’s promise for strong deliverability solutions has created a niche for itself in the email delivery scene. What then occurs when the delivery rates fall short of your expectations?

    We are delving further into the field of email deliverability in this post since companies depending on email communications need this essential capacity to properly reach consumers. We will investigate why Postmark may be seeing lower than expected deliverability rates despite its popularity and promises as well as why the measures used to document these rates might not always provide the whole picture. From technological difficulties to policy obstacles and beyond, join us as we expose the layers underlying what makes — or breaks — the delivery of your digital mail.

    Realizing email deliverability

    The measure of an email’s success in reaching the recipient’s inbox — avoiding filters and dangers like the spam folder or being flatly refused by the email server — is email deliverability. For companies and marketers, this is a crucial statistic since, even the best-written email is pointless if it never finds its target recipient. The stakes are considerable: One of the most successful marketing tools available, direct marketing association statistics show email marketing usually returns on investment of roughly $42 for every dollar spent.

    Several important criteria are used to evaluate email deliverability:

    • Track the percentage of sent emails that might not have reached the recipient’s inbox using bounce rate. Usually indicating problems with the email list or email server, a high bounce rate points to
    • The open rate—that is, the proportion of emails opened by recipients—measures Although open rates are helpful, the way contemporary email applications handle tracking pixels—used to gauge opens—may make them misleading.
    • Complaints about spam come from receivers marking an email as such. Since it influences a sender’s future deliverability and reputation, this statistic is absolutely crucial.

    Email deliverability over all platforms can be affected by several elements, including:

    • Sender Reputation. Based on emailing behavior, this score is issued to senders akin to credit scores. This score is affected by elements like volume, frequency, and user involvement—that is, openings and clicks.
    • Emails triggering spam filters because of certain keywords or bad formatting will have reduced deliverability.
    • Maintaining good deliverability can depend on routinely cleaning the email list to eliminate inactive or unresponsive email addresses.
    • Tools like SPF, DKim, and DMARC enable sender identity verification and are absolutely essential in avoiding emails from being marked as spam.

    Analysis of Postmark’s deliverability issues

    Postmark deliverability

    Postmark is renowned for its commitment to high deliverability rates, making any issues in this area particularly noteworthy. Users have reported sporadic problems, which range from sudden spikes in bounce rates to significant delays in email delivery times. Such inconsistencies can be puzzling, given Postmark’s reputation and the robust infrastructure it promises.

    When examining Postmark’s performance metrics against industry standards, several discrepancies become apparent. Typically, industry benchmarks for bounce rates are kept below 2%, and a good open rate ranges anywhere from 15% to 25%. However, some Postmark users have observed bounce rates occasionally climbing higher than this threshold without clear explanations, which could indicate underlying issues with how Postmark manages sender reputations or handles IP addresses.

    Moreover, the accuracy of Postmark’s reported metrics has come into question. Open rates, as reported by Postmark, are often in flux, which might be attributed not only to the actual recipient behaviors but also to how email clients and devices report back to tracking systems. The lack of consistent reporting standards across the industry makes it challenging to gauge true performance accurately.

    Potential Causes of Low Deliverability in Postmark

    Low email deliverability can significantly impact a business’s ability to engage with its audience effectively. For a service like Postmark, known for its robust email delivery capabilities, encountering issues with deliverability can stem from a variety of sources

    Technical Issues

    These can be some of the most disruptive factors affecting email deliverability. Server downtime or instability within Postmark’s infrastructure can delay or prevent emails from reaching recipients. Additionally, IP reputation problems are critical; if Postmark’s IP addresses are flagged by major ISPs or blacklisted due to the activities of other users sharing the same server, even legitimate emails can end up being blocked or sent to spam folders.

    Policy and Compliance Challenges

    Postmark’s adherence to strict compliance policies, while beneficial for maintaining standard protocols, can sometimes backfire. For example, overly stringent rules may lead to legitimate emails being categorized as spam. Similarly, if Postmark’s system for managing spam complaints and bounce rates is not finely tuned, it could lead to incorrect flagging of sender addresses, further harming deliverability.

    Integration and Configuration Errors

    Errors in setup are common pitfalls that can affect deliverability. Users might incorrectly configure their domain’s SPF, DKIM, and DMARC records, which are crucial for authentication and preventing spoofing and phishing attacks. Misconfigurations can lead ISPs to mistrust the sender, leading to emails being rejected or marked as spam.

    Volume and Content Concerns

    The volume of emails sent and the content within them can also impact deliverability. High volumes of email sent in short bursts can trigger spam filters, especially if the sending patterns appear erratic or don’t follow typical engagement practices. Content that includes certain trigger words, poor HTML coding, or overly sales-oriented language can also increase the likelihood of being filtered into spam.

    Questioning the Accuracy of Deliverability Metrics

    Deliverability metrics like open rates and bounce rates are absolutely vital in email marketing for evaluating general email performance and campaign effectiveness. Accurately assessing these criteria does, however, provide various difficulties, and occasionally this results in differences in the stated figures—including those from Postmark.

    Challenges in Measuring Open Rates

    Open rates are typically tracked using a small, invisible image pixel that loads when the recipient opens the email. However, this method isn’t foolproof:

    • Email Clients Blocking Images. Many email clients block images by default, which prevents the tracking pixel from loading and thus, the open is not recorded.
    • Use of Text-Only Emails. Text-only emails do not support the use of tracking pixels, so opens of these emails are not recorded at all.
    • Automatic Image Loading. Conversely, some modern email clients automatically load images before the user actually opens the email, which can falsely inflate open rates.

    Factors Contributing to Inaccuracies in Postmark’s Reported Numbers

    • IP and Domain Reputation. Fluctuations in IP and domain reputation can impact deliverability and, consequently, the accuracy of metrics. For instance, if emails are being sent from an IP address that gets blacklisted, subsequent emails might be blocked or sent to spam folders, skewing open and bounce rates.
    • User Engagement Misinterpretation. Postmark and similar services might misinterpret indirect signals of engagement. For instance, a user moving an email out of the spam folder could be counted as an open, which does not necessarily indicate genuine engagement.
    • Reporting Delays. Delays in data processing and reporting can also lead to inaccuracies. If emails are opened after a significant delay from the time they were sent, these opens might not be accurately captured in real-time reports.

    Comparisons with competitors

    When evaluating the effectiveness of email delivery services, it’s useful to compare Postmark with other major providers like SendGrid and Mailgun. These comparisons not only shed light on deliverability rates but also highlight the different features that can influence email deliverability success.

    Deliverability Rates Comparison

    • Postmark is often praised for its high deliverability rates, with claims of achieving over 99% deliverability. This is a testament to its robust infrastructure and strong emphasis on sender reputation management.
    • SendGrid, another leader in the space, similarly reports high deliverability rates. They have extensive scalability options which are ideal for large volume senders, potentially offering better rates for these users through dedicated IP addresses.
    • Mailgun markets itself with a strong focus on developers and technical integrations, claiming deliverability rates on par with other industry leaders. It offers both shared and dedicated IP options, which can significantly impact deliverability depending on the user’s needs.


    Comparative Analysis of Features Influencing Deliverability

    • Authentication and Compliance. All three services provide comprehensive tools for managing SPF, DKIM, and DMARC records, which are essential for improving email authentication and thereby deliverability. However, the ease of setup and management can vary, with Postmark often recognized for its user-friendly interface.
    • IP Management. SendGrid and Mailgun offer the option to use dedicated IPs, which can help large volume senders maintain their reputation and thus their deliverability. Postmark typically manages this behind the scenes, offering a more hands-off approach which can be preferable for smaller senders or those less familiar with the intricacies of IP reputation.
    • Analytics and Reporting. SendGrid provides detailed analytics and real-time monitoring tools that can help users quickly identify and rectify issues that might affect deliverability. Postmark and Mailgun also offer analytics, though the depth and usability of reporting can differ, affecting how quickly users can respond to deliverability issues.
    • Customer Support and Resources. The level of support provided can directly affect how effectively companies can manage deliverability issues. Postmark is noted for its responsive customer support. SendGrid and Mailgun also provide extensive documentation and support, but the responsiveness and personal touch can vary.

    Solutions and tools for improving deliverability

    Improving email deliverability is crucial for ensuring that your communications reach their intended recipients. By employing best practices and utilizing advanced tools like Warmy.io, businesses can significantly enhance their email performance. Here’s a detailed look at some strategies and tools available:

    Best Practices for Postmark Users

    For those utilizing Postmark to manage their email campaigns, several key practices can help maximize deliverability:

    • Regular List Cleaning. Remove inactive or unresponsive email addresses periodically. This reduces bounce rates and improves overall sender reputation.
    • Optimize Email Content. Avoid spam-trigger keywords, use clear and compelling subject lines, and ensure the email body is engaging and well-formatted. This helps in bypassing spam filters.
    • Use Segmentation. Tailor your emails to specific segments of your audience based on their behaviors and preferences. This not only enhances engagement but also boosts open rates.
    • Monitor Feedback Loops. Set up feedback loops with ISPs to receive notifications when recipients mark your emails as spam. This insight allows you to adjust strategies and avoid those users in future campaigns.
    • Implement Authentication Protocols. Ensure SPF, DKIM, and DMARC records are properly set up and validated. This improves your emails’ legitimacy and trustworthiness in the eyes of email service providers.

    Using Warmy.io

    email warm up

    Warmy.io is designed to “warm up” your email accounts by automatically sending and receiving emails that mimic genuine interactions. This gradual increase in email activity helps in building a solid sender reputation, crucial for improving deliverability rates.

    Warmy.io encourages new users to explore its capabilities with a 7-day free trial, allowing them to gauge the effectiveness of the tool without initial investment.

    Additionally, Warmy.io offers free tools critical for email health

    • SPF and DMARC Record Generator. These tools help users correctly set up email authentication measures, which are vital for preventing emails from being flagged as spam.
    • Email Deliverability Test. Users can check how likely their emails are to hit the inbox and get actionable advice on how to fix issues that might prevent that.
    • Email Template Checker. This tool analyzes whether an email’s content could trigger spam filters, helping users make necessary adjustments before sending.

    By implementing these best practices and leveraging tools like Warmy.io, businesses can tackle the common challenges in email deliverability, ensuring their communications are both seen and interacted with by their audience. For more information on how to get started, visit Warmy.io.


    Maintaining high email deliverability is not only a technical need but also a fundamental element of effective digital communication plans.

    Selecting the proper email distribution system is equally important. As we have shown, Postmark is not without flaws even if it provides strong tools and generally great delivery. The variations among providers such as SendGrid, Mailgun, and Postmark underline the need of appreciating the particular strengths and possible shortcomings of any platform. The decision should fit the particular requirements of a business, including volume, type of emails sent, technical support, and advanced tools meant to help keep compliance with best practices and a decent sender reputation.

    Moreover, the effectiveness of a platform can be much improved by using extra tools like Warmy.io. These instruments not only warm up email accounts but also guarantee continuous technical standard compliance with SPF, DKim, and DMARC—all of which are absolutely essential for contemporary email marketing.

    The path to outstanding email deliverability is, all things considered, continuous and complex. It combines selecting the correct provider, always adjusting to changing email environments, and applying creative techniques to maximize every facet of email conversation. This helps companies to protect their capacity to effectively interact with their audience, thereby guaranteeing that their messages are both visible and appreciated.

    📜 Related article:


    What is Postmark deliverability?

    Postmark deliverability refers to the ability of emails sent through Postmark to successfully reach the intended recipients' inboxes without being filtered out as spam or bounced back.

    Why is my Postmark deliverability rate low?

    Low deliverability rates in Postmark can be caused by several factors, including poor sender reputation, issues with email content triggering spam filters, lack of proper email authentication (SPF, DKIM, DMARC), and high bounce rates due to outdated or incorrect email addresses.

    How can I improve my email deliverability with Postmark?

    To enhance your Postmark deliverability, ensure your email lists are clean and up-to-date, authenticate your emails using SPF, DKIM, and DMARC, monitor your sender reputation, and avoid spammy content. Regular testing and adjustments based on feedback and metrics are also crucial.

    Does Postmark offer tools to help with deliverability?

    Yes, Postmark provides several tools to aid in improving deliverability, including feedback loop setup, detailed analytics to monitor opens, clicks, and bounces, and guidelines for best email practices.

    How does Postmark handle IP reputation?

    Postmark manages IP reputation through meticulous monitoring and proactive management. They use dedicated IP pools based on customer sending behavior, which helps in maintaining a strong reputation and thus better deliverability.

    What should I do if my emails are getting marked as spam in Postmark?

    If your emails are marked as spam, review your email content for potential red flags, ensure compliance with Postmark's sending policies, and check your email authentication setups. You may also need to contact Postmark support for specific insights and solutions based on your account activity.

    What is the best way to use Postmark for maximum deliverability?

    For optimal deliverability with Postmark, use warm up services like Warmy.io, prioritize email authentication, maintain a healthy sender reputation, regularly clean your email lists, and follow the best practices provided by Postmark. Engaging professionally with recipients to ensure they expect and want your emails can also significantly boost deliverability.

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