Email throttling controls how quickly your emails are sent. It’s an important deliverability tool, helping you balance sending speed with inbox placement and sender reputation.
You might look for a specific throttling number - for example, “send 100 per hour for eight hours per day”. In practice, though, there isn’t a single rate that works for every sender. The right throttling speed depends on your goals, timing, and sending reputation, which can vary significantly from account to account.
Because of this, throttling is best approached as a flexible setting rather than a fixed number.
Factors to consider when setting your throttling speed
Several factors affect how quickly you should send your emails:
Your delivery deadline. If your campaign must be completed by a specific time - for example, before an event starts - your throttling should allow all emails to be sent before that point. But if that were extraordinarily fast compared to your regular sending, it would risk the major email providers blocklisting you and many of all of your emails from that point onward never reaching the inbox, only spam folders.
How firm that deadline really is. A newsletter, for instance, can be sent gradually throughout the week or even across a month without issue. In fact, if you send your monthly newsletter to the same audience at the same start time each month, each contact would typically receive it at roughly the same time month after month.
Your current send rate. You can see this in your Deliverability Report under “Daily Volume”. Some quick maths may be needed to calculate how many emails are being sent per hour and how many hours per day your sends are active.
Why we recommend “as slow as possible while meeting the deadline”
If your IP address or domain is new, it needs to be warmed up before sending large volumes. Warming up gradually helps build trust with receiving mail servers and prevents your messages from being flagged as spam.
Because each sender’s reputation and history are unique, we can’t set a one-size-fits-all number. That’s why our best practice advice will always be to send as slowly as possible while still meeting your campaign deadline.
Think slow. If it's at all possible to start with double digits per hour, do so.
What’s happening behind the scenes
We aren’t privy to the exact algorithms used by large mailbox providers like Gmail, Outlook, or Yahoo. Their systems continuously evolve to detect and filter spam.
That means sending too quickly, before your reputation is established, increases your risk of spam filtering or blocklisting. The safest approach is to:
Start slowly.
Monitor your deliverability reports and spam placement over time.
Gradually increase your sending speed once you see stable inbox placement.
Building up a strong sending reputation that supports higher volumes can take months - this is not a Force24 limitation but a reality of modern email marketing. In recent years, major email providers have become much stricter about sender reputation and consistency.
For more on this, see:
Key takeaway
There is no universal “safe” throttling number. The right rate depends on your reputation, your sending history, and your deadline. Always send as slowly as you can while achieving your goal, and keep a consistent pattern to strengthen your sender reputation over time.