What are the best practices for email deliverability when using SparkPost and Amazon SES, including reverse DNS, blacklist monitoring, and handling dedicated IPs?

Summary

Achieving optimal email deliverability with SparkPost and Amazon SES requires a multifaceted approach. Begin by verifying all sender email addresses via AWS SES. Implement proper reverse DNS (rDNS) configuration, ideally matching hostnames, especially when using dedicated IPs. Leverage ESP-provided metrics dashboards for day-to-day monitoring. Maintain a positive sender reputation through email authentication (SPF, DKIM, DMARC), relevant content, and minimal spam complaints. Implement DMARC policy enforcement to prevent domain spoofing. Warm up dedicated IPs gradually, starting with engaged subscribers, while closely monitoring bounce rates and complaints. Prioritize email list hygiene by removing inactive, invalid, and risky addresses; utilize email validation services. Actively monitor blacklists, focusing on prominent lists like Spamhaus, and set up feedback loops with ISPs to manage spam complaints. Ensure proper bounce handling, suppression lists, and consider using email testing tools like GlockApps to proactively identify and resolve deliverability issues. Finally, implement robust bounce processing and DKIM key configurations with appropriate key sizes, coupled with regular key renewals.

Key findings

  • Email Authentication: Consistent authentication using SPF, DKIM, and DMARC significantly improves deliverability and sender reputation.
  • Reverse DNS (rDNS): Properly configured rDNS that matches your sending domain enhances trust and deliverability, especially with dedicated IPs.
  • Sender Reputation: Maintaining a positive sender reputation is crucial, as ISPs use it to determine email acceptance and inbox placement.
  • Blacklist Monitoring: Monitoring blacklists, particularly Spamhaus, is vital for identifying and addressing issues affecting sending IPs or domains.
  • IP Warming: Warming up dedicated IPs gradually helps establish a positive sending reputation with ISPs.
  • Email List Hygiene: Practicing good email list hygiene improves deliverability by removing inactive, invalid, and spam trap addresses.
  • Suppression Lists: Suppression lists automatically prevent sending to addresses that have bounced, unsubscribed, or marked emails as spam.
  • Email Testing: Email testing tools help identify deliverability issues, such as placement in spam folders, before sending campaigns.
  • DMARC Policy: Implementing DMARC policy enforcement prevents unauthorized domain usage and greatly enhances deliverability.

Key considerations

  • AWS SES Verification: Verify each email address (sender) before using it to send email through Amazon SES.
  • ESP Metrics: If paying SparkPost or SES, leverage their provided user-friendly metrics dashboards for day-to-day monitoring.
  • Spamhaus Listings: Getting listed by Spamhaus requires immediate attention, but resolving the issue can lead to quick delisting.
  • Bounce Handling: Set up bounce notifications and promptly remove bouncing addresses from your sending lists.
  • Engaged Subscribers: Start with your most engaged subscribers when warming up IPs, monitoring bounce rates and spam complaints.
  • 2048 Bit DKIM: Implement a 2048-bit DKIM key, which increases security; also, ensure you renew keys regularly.

What email marketers say
11Marketer opinions

To achieve optimal email deliverability when using SparkPost and Amazon SES, several best practices should be followed. It's critical to maintain a positive sender reputation through consistent email authentication (SPF, DKIM, DMARC), sending relevant content, and managing subscriber lists effectively. Actively monitor blacklists and swiftly address any listings. Ensure proper reverse DNS (rDNS) configuration, especially when using dedicated IPs. Implement a strategy for warming up new IPs by gradually increasing sending volume to engaged subscribers. Practice good email list hygiene by removing inactive or invalid addresses, and employ email validation services for ongoing list maintenance. Use email testing tools to proactively identify and resolve deliverability issues. Finally, establish feedback loops and promptly handle bounces to maintain a clean sending reputation.

Key opinions

  • Sender Reputation: Maintaining a positive sender reputation is crucial as ISPs use it to determine whether to accept, reject, or filter emails.
  • Authentication: Consistently authenticate your emails using SPF, DKIM, and DMARC to improve deliverability.
  • Reverse DNS: Properly configure reverse DNS (rDNS) for your sending IPs, especially dedicated IPs, to match your domain and enhance trust.
  • Blacklist Monitoring: Regularly monitor blacklists to identify and address any listings affecting your sending IPs or domain.
  • IP Warming: When warming up new IPs, gradually increase sending volume to engaged subscribers to establish a positive reputation.
  • List Hygiene: Practice good email list hygiene by removing inactive, invalid, and risky email addresses.
  • DMARC Enforcement: Implement DMARC policy enforcement to prevent unauthorized use of your domain and enhance sender reputation.
  • Email Validation: Use email validation services to remove invalid, risky, and inactive addresses, which will protect sender reputation.

Key considerations

  • Dedicated IPs: If sending from IPs through Sparkpost/SES and those IPs appear in Received headers, ensure valid rDNS is set.
  • Spamhaus Listing: Being listed on Spamhaus is a significant concern, but prompt action to resolve the issue will lead to delisting.
  • Content Relevance: Ensure your email content is relevant and targeted to your subscribers to minimize spam complaints.
  • Suppression Lists: Utilize suppression lists (bounces, unsubscribes, spam complaints) to avoid sending to problematic addresses.
  • Email Testing: Use email testing tools before sending campaigns to identify and fix deliverability issues.
  • Engaged Subscribers: When warming IPs, start with the most engaged subscribers, and increase volume as confidence grows.
Marketer view

Email marketer from ZeroBounce shares that regular email validation removes invalid, risky, and inactive email addresses from your list to protect your sender reputation and improve deliverability. ZeroBounce can help with this process.

July 2021 - ZeroBounce
Marketer view

Email marketer from GlockApps explains that using email testing tools like GlockApps before sending campaigns helps identify deliverability issues, such as placement in spam folders, allowing you to make necessary adjustments.

April 2023 - GlockApps
Marketer view

Email marketer from Senderverify explains that to improve sender reputation, consistently authenticate your emails, maintain low spam complaint rates, send relevant content, and remove inactive subscribers.

February 2023 - Senderverify
Marketer view

Email marketer from Reddit shares that when warming up IPs, start with your most engaged subscribers and gradually increase volume. Monitor bounce rates and spam complaints closely during this process.

October 2023 - Reddit
Marketer view

Email marketer from Mailjet Blog explains that sender reputation is crucial for deliverability. ISPs use it to determine whether to accept, reject, or filter your emails. Positive reputation leads to better inbox placement.

August 2023 - Mailjet Blog
Marketer view

Email marketer from Litmus explains that practicing good email list hygiene improves deliverability. This involves regularly cleaning your list by removing inactive subscribers, invalid email addresses, and spam traps.

October 2023 - Litmus
Marketer view

Email marketer from SMTP2GO shares that monitoring blacklists helps you identify if your sending IPs or domain have been listed, which can significantly impact deliverability. Prompt action is needed to resolve listings.

July 2024 - SMTP2GO
Marketer view

Email marketer from Email Marketing Forum explains that when setting up dedicated IPs with SES or SparkPost, ensure proper rDNS configuration that matches your sending domain. This improves trust and deliverability.

October 2024 - Email Marketing Forum
Marketer view

Email marketer from Email Geeks shares if you're sending from IPs through Sparkpost/SES and those IPs appear in Received headers, make sure you set valid rDNS on those too.

October 2023 - Email Geeks
Marketer view

Email marketer from Email Geeks shares that Spamhaus is a big deal and getting listed by them should be taken seriously. However they will immediately delist you if you solve the problem. Steve adds that you will likely know from other metrics fast if you get listed.

April 2024 - Email Geeks
Marketer view

Email marketer from EasyDMARC explains that implementing DMARC policy enforcement (p=quarantine or p=reject) prevents unauthorized use of your domain in email, greatly enhancing sender reputation and deliverability.

March 2025 - EasyDMARC

What the experts say
7Expert opinions

To optimize email deliverability with SparkPost and Amazon SES, focus on several key areas. Ensure reverse DNS (rDNS) is properly configured to match your sending domain, use ESP provided monitoring tools for everyday deliverability, and address publicly accessible blacklists such as Spamhaus. Maintain good list management and engagement practices by avoiding sending to unengaged users, and configure robust bounce processing with your ESP by whitelisting their IPs. Also, implement strong DKIM keys (2048 bit) and ensure regular key renewal for enhanced security and deliverability.

Key opinions

  • Reverse DNS Configuration: Reverse DNS should match the hostnames of your machine and the name given in the EHLO to avoid filters being wary.
  • ESP Monitoring Tools: If using SparkPost or SES, leverage the provided metrics dashboards for day-to-day monitoring of deliverability.
  • Blacklist Impact: Spamhaus lists are one of the most impactful public blacklists and can directly effect delivery problems.
  • List Management: List management and engagement is key, sending to unengaged users can damage your reputation.
  • DKIM Key Size: Using a 2048 bit DKIM key and regular renewal improves deliverability by adding increased security.

Key considerations

  • Spamhaus Reputation: Spamhaus has a strong reputation and is widely used due to its reasonable listing policies and professional conduct.
  • Bounce Processing: Proper bounce processing and whitelisting of your ESP's IPs are crucial for reliable feedback and to prevent blocking legitimate traffic.
Expert view

Expert from SpamResource shares that one of the most important aspects of deliverability is list management and engagement. Sending to unengaged users can damage your reputation and land you in the spam folder.

June 2022 - SpamResource
Expert view

Expert from Email Geeks explains that if you’re paying Sparkpost or SES to send your mail, setup and monitoring is their responsibility. They should provide user-friendly metrics dashboards for day-to-day use. Access to raw data is useful for diagnosing problems but not needed constantly.

November 2022 - Email Geeks
Expert view

Expert from Email Geeks explains that reverse DNS should ideally match the hostnames of your machine and the name given in the EHLO. While it's primarily for tidiness, some filters are wary of generic or missing reverse DNS. Examples like mail1.yourcorpdomain.com are good, while he-208-187-80-130.whatever.com are bad.

October 2022 - Email Geeks
Expert view

Expert from SpamResource explains that setting a 2048 bit DKIM key is critical to improving deliverability. Using a larger key size helps give increased security. Also to make sure you renew keys regularly.

May 2023 - SpamResource
Expert view

Expert from SpamResource explains that setting up proper bounce processing with your ESP and whitelisting their IPs is crucial for deliverability when using services like SparkPost and Amazon SES. This ensures reliable feedback and prevents accidental blocking of legitimate traffic.

January 2024 - SpamResource
Expert view

Expert from Email Geeks explains Spamhaus has reasonable listing policies and has been pleasant and professional to deal with, leading to wide trust and use, and a significant and immediate effect on email delivery.

November 2023 - Email Geeks
Expert view

Expert from Email Geeks explains that of the publicly accessible blacklists, Spamhaus lists and maybe URIBL are the ones expected to have a direct effect on delivery problems.

September 2022 - Email Geeks

What the documentation says
6Technical articles

To ensure optimal email deliverability when using SparkPost and Amazon SES, it's critical to adhere to established best practices. Verification of all sender email addresses is a mandatory first step within the AWS SES platform. When utilizing dedicated IPs, a gradual warm-up process involving incrementally increasing sending volume over weeks is advised by SparkPost to build a positive sender reputation with ISPs. Implementing SPF records by publishing a TXT record in your DNS settings is vital for authenticating your email. The utilization of suppression lists to automatically exclude bounced, unsubscribed, or spam-complaining addresses is necessary. Proactive bounce handling through the configuration of bounce notifications and subsequent removal of bouncing addresses from mailing lists further contributes to a healthy sender reputation. Finally, configuring feedback loops with ISPs to receive spam complaint reports allows for the identification and removal of problematic subscribers, thereby upholding overall deliverability standards.

Key findings

  • Email Verification: You must verify each sender email address before using it with Amazon SES.
  • IP Warming: Gradually increase sending volume over several weeks when using dedicated IPs to establish a positive reputation.
  • SPF Records: Set up SPF records by publishing a TXT record to your DNS to authorize mail servers to send on behalf of your domain.
  • Suppression Lists: Suppression lists are essential for automatically excluding addresses that have bounced, unsubscribed, or marked emails as spam.
  • Bounce Handling: Proper bounce handling is crucial and involves setting up notifications and removing bouncing addresses from your sending lists.
  • Feedback Loops: Setting up feedback loops with ISPs allows receiving spam complaint reports to identify and remove problematic subscribers.

Key considerations

Technical article

Documentation from SparkPost explains that suppression lists are essential for maintaining deliverability. These lists automatically prevent sending to addresses that have bounced, unsubscribed, or marked your emails as spam.

February 2024 - SparkPost Documentation
Technical article

Documentation from AWS explains that to set up SPF records, you need to publish a TXT record to your DNS server that specifies the mail servers that are authorized to send email on behalf of your domain.

August 2024 - AWS Documentation
Technical article

Documentation from SparkPost explains that warming up dedicated IPs gradually increases your sending volume to establish a positive sending reputation with ISPs. They recommend starting with small volumes and gradually increasing them over several weeks.

May 2021 - SparkPost Documentation
Technical article

Documentation from SparkPost explains that setting up feedback loops with ISPs allows you to receive reports of spam complaints. This helps you identify and remove problematic subscribers from your list.

December 2023 - SparkPost Documentation
Technical article

Documentation from AWS explains that you must verify each email address (sender) before you can use it to send email through Amazon SES. You can verify email addresses by using the Amazon SES console or by using the Amazon SES API.

February 2022 - AWS Documentation
Technical article

Documentation from AWS explains that proper bounce handling is crucial. Set up bounce notifications and remove bouncing addresses from your sending lists promptly to maintain a healthy sender reputation.

December 2023 - AWS Documentation