Skip to main content
Skip table of contents

Email delivery speed

We handle the delivery of millions of emails every day from multiple clients. You may want to know how fast that your emails will be delivered when you send email campaigns and automations, especially if you have a large supporter database. 

Our two mail servers have delivered emails at peak capacities of 200,000 per minute based on the latest data from mid-2019, and for crucial delivery days such as Giving Tuesday, we’ve delivered as many as 57 million emails in a 24-hour period (as we did in 2021).

That said, as a metric by itself, email volume doesn’t satisfactorily reflect good email deliverability. There are a multitude of other factors that go into making sure emails land in inboxes, including:

  • Email throttling
  • Bounce management and suppression criteria
  • Blacklist and block mitigation
  • Email authentication
  • Sender reputation monitoring

For example, it can be beneficial to actually limit the number of emails that are sent to certain domains in a given timeframe. Where any limits are imposed on sending volumes by mailbox providers, using roll-up queues effectively ensures that emails are delivered at the rate specified by a provider, which in turn maximises deliverability and minimises bounces.

We also provide tools that allow users to manage how their emails are authenticated with providers. Users can employ settings that ensure their throughput of mail across our server is ‘whitelabelled’ with their domain through DKIM authentication, the sender envelope, and the return path to fortify delivery and maximise inbox placement.

Where there are deliverability issues with email, they usually present themselves as hard bounces or spam placement and, when these issues do present themselves, sending more emails per minute will make that problem worse rather than better. Our tools and services are engineered to manage very high delivery volumes at peak times, but first and foremost we want to ensure that those volumes reach their target.

JavaScript errors detected

Please note, these errors can depend on your browser setup.

If this problem persists, please contact our support.