Rapid fire

Reduce ESP email throttling

With Mailgun’s email throttling management, get optimized deliverability for large senders (500k+/month). Make sure your emails have the best chance of landing in inboxes with Mailgun’s custom sending limits per major ESP based on experience, analytics, and feedback.

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Customized delivery plan for optimal email performance

If 100% email deliverability is your goal, we need to talk. Great deliverability is about sending the right emails, to the right people, the right way. That means not letting email throttling cause delayed or blocked email deliveries, reduce audience reach, decrease engagement rates, or harm your sender reputation.

Sign up for a unique and customized discovery session with your team, with a detailed delivery plan based on the unique aspects of your business and email sending needs.

We send 10+ billion emails every month so we know a thing or two about best practices and how to best reach your users.

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Proactive email reputation management

Sending millions of emails a month requires an extra level of diligence to maintain a positive sending reputation. A single misstep can send a big part of your email to spam. That’s where an appropriate email throttling strategy comes in.

Avoid costly mistakes without the need for expensive certifications with expert monitoring of your email deliverability around the clock. If anything’s wrong, you’ll know ASAP.

Automated systems check if your sending domain gets on a blocklist. Plus you’ll have dedicated access to our deliverability experts who can help get your emails where they belong, the inbox.

Integrations

Other great features of Managed Email support

Deliverability and recipient engagement management

Optimize for higher opens and clicks in collaboration with an email expert assigned to your account.

Managed IP warmup

Ensure the health of your IPs by customizing your warm up plan to your specific needs.

Sending infrastructure consulting

Enjoy a constant feedback loop between your TAM, Mailgun developers, and your team with infrastructure consulting.

Custom reverse DNS on all your IPs

Achieve the ideal domain and IP setup that will set you up for a stronger sending reputation.

IP allocation management

Send with confidence knowing you have the right mix of dedicated and shared IPs for your email volume and use case.

Proactive monitoring of your email program

Get the peace of mind that comes with having a dedicated expert monitoring your email sending for any hiccups.

Email tracking and testing consulting

Get expert advice on what your open rate, click rate, and other metrics really mean so you can optimize your performance.

High-quality dedicated IP subnets

Take care of even the largest email sends effortlessly with IP subnets that can handle burst sending.

FAQ

Frequently asked questions

Email throttling limits the number of emails sent over a specific period to avoid triggering spam filters or exceeding recipient server limits. It helps with email deliverability and compliance with ISP rules.

Email providers throttle messages to prevent spam, reduce server load, and protect their infrastructure from abuse. They often limit the volume or frequency of messages from unfamiliar or high-volume senders. 

Signs of throttling include:

  – Delayed email delivery

  – Temporary SMTP error codes (like 421 or 451)

  – Bounce messages indicating “too many messages” or “rate limited”

Monitoring your email logs and ISP feedback can help confirm throttling. 

Most major email services like Gmail, Yahoo, Outlook, and AOL use throttling to protect users from spam and maintain service quality. Each provider has its own policies and thresholds.

To prevent throttling:

  – Warm up your IP gradually.

  – Use dedicated IPs for large volumes.

  – Follow email sending best practices.

  – Monitor bounce and complaint rates.

  – Comply with ISP-specific sending limits. 

Email throttling and rate limiting are similar, but throttling adjusts sending speed dynamically based on server response or policies.

Rate limiting imposes fixed caps on sending volume per time period, regardless of server behavior. 

Email throttling can improve deliverability when done correctly by reducing the chance of hitting spam traps or getting blacklisted. However, aggressive throttling by ISPs may delay or block messages if senders don’t follow best practices.