What are the best practices for handling throttling from new IPs and recipient domains?

Marketer from Email Geeks advises that 100,000 messages per hour per IP is a more realistic target than 1,000,000 which is only achievable by the highest reputation senders.

Email marketer from Mailjet shares that it is important to monitor sender reputation metrics, such as bounce rates and spam complaints, to identify and address any issues that could lead to throttling. Implementing feedback loops and promptly removing unsubscribed recipients can help maintain a positive reputation.

Email marketer from SendGrid shares that segmenting email lists based on subscriber engagement and sending targeted emails to active subscribers can improve deliverability and reduce the risk of throttling. This approach ensures that emails are sent to recipients who are more likely to engage with the content.

Email marketer from Gmass states that as you increase volume, do it slowly and steadily. Increasing your sending volume by 50-100% in a day or week is likely to raise alarms. It is suggested to double your daily send amount weekly, not daily.

Email marketer from HubSpot explains that regularly cleaning email lists to remove inactive or invalid email addresses can improve deliverability and reduce the risk of throttling. Sending emails to engaged subscribers ensures that deliverability rates remain high.

Email marketer from Litmus explains focusing on delivering valuable and relevant content to subscribers can improve engagement and reduce the likelihood of throttling. High-quality content encourages recipients to open and interact with emails, signaling positive intent to recipient domains.

Email marketer from Woodpecker shares that you should monitor your sender reputation. Use tools like Google Postmaster Tools or Sender Score to assess your reputation. Address any issues that arise promptly to maintain good standing with email providers.

Email marketer from Email Marketing Forum explains that closely monitoring bounce rates and complaint rates provides insights into deliverability issues. High bounce and complaint rates can trigger throttling, so it's essential to address them promptly to maintain a good sender reputation.

Marketer from Email Geeks states that orange.fr has a limit of 3 simultaneous connections.

Email marketer from Campaign Monitor shares avoiding spam triggers in email content and subject lines can help prevent emails from being flagged as spam and throttled by recipient domains. This includes refraining from using excessive punctuation, all caps, and misleading language.

Marketer from Email Geeks says that receivers prefer to have more messages per connection than having a lot of connect/disconnect, and suggests 500 messages as a good balance.

Email marketer from Reddit responds that encouraging subscriber engagement through personalized content and interactive elements can improve sender reputation and reduce the likelihood of throttling. High engagement rates signal to recipient domains that the email is valuable and desired by recipients.

Marketer from Email Geeks states that orange.fr AND wanadoo.fr, the two combined have a max of 3 connections.

Expert from Email Geeks recommends backing off to the level where sending was successful for 2-3 days and states that if getting ‘too many messages from new IP’ it means the warmup is too fast.

Expert from Email Geeks explains connection limiting is usually based on how many times a particular IP has opened any connection to their MX machines, so it’s per MX not per receiving domain.

Expert from Word to the Wise explains greylisting, a technique used by recipient domains to temporarily defer emails from unknown senders, can appear as throttling. They suggest configuring email servers to retry sending deferred emails and implementing proper IP warm-up procedures to establish a positive reputation.

Expert from Email Geeks states a normal expectation is 1 million per IP per day.

Expert from Word to the Wise responds that participating in feedback loops (FBLs) provided by major ISPs allows senders to receive reports about spam complaints, enabling them to identify and remove abusive recipients from their lists. FBLs help maintain a clean sending reputation and reduce the risk of throttling.

Expert from Spamresource explains that understanding SMTP error codes (4xx errors) is essential for identifying throttling issues. They recommend monitoring these errors to identify patterns and adjust sending practices to avoid exceeding recipient domain limits.

Expert from Spamresource advises implementing a robust bounce management system to handle temporary and permanent failures effectively. Processing bounces and removing invalid addresses helps maintain a clean sending reputation and reduces the likelihood of throttling.

Expert from Email Geeks explains the best thing to do, particularly if using momentum, is to let the MTA handle throttling as the built in ruleset is more up to date and accurate than manual throttling.

Documentation from Microsoft answers implementing email authentication protocols such as SPF, DKIM, and DMARC can help verify the sender's identity and prevent email spoofing, which can lead to throttling. These protocols provide assurance to recipient domains that the email is legitimate and not spam.

Documentation from SparkPost responds that limiting the number of concurrent connections to recipient domains can help prevent throttling. They suggest implementing connection pooling and reusing connections to reduce the overhead of establishing new connections for each email.

Documentation from RFC Editor explains that understanding and adhering to SMTP rate limits imposed by recipient domains is crucial for avoiding throttling. Respecting these limits ensures that email traffic is distributed evenly and does not overwhelm recipient servers, preventing throttling.

Documentation from Google explains that gradually increasing the volume of email sent from a new IP address, known as IP warm-up, is crucial to establishing a positive reputation with recipient domains and avoiding throttling. Start with small volumes and gradually increase it over weeks.

Documentation from AWS says to monitor your sending activity. Most email service providers (ESPs) offer dashboards and reports that allow you to monitor your sending activity. Keep an eye on your bounce rate, complaint rate, and other metrics.