Rate limiting and sequence recipient limits
What is rate limiting?
Sequences are fantastic for automating outreach and communications to hundreds of contacts. However, if you try to send to too many people at once, you might hit Gmail's imposed rate limits — this means your account could be limited if you send a high volume of messages in a short period of time. Because Mixmax sends your messages through your Gmail account, Mixmax is subject to any limitations set by Google, including rate-limiting. Google monitors the rate at which messages are sent through your account messages, not just the total number of messages you send in a 24-hour period.
To prevent this from happening, we have a sophisticated algorithm that makes it look to Gmail like you're sending the messages manually (although the Mixmax AI is doing it for you:). If you upload a recipient list with more than 500 recipients we'll space out the sending, over multiple weekdays, sending to 500 recipients per day. We send the messages individually, and space them out over time. If you want to send to more than 2,000 recipients, we recommend sending in batches, a few days apart.
If you routinely send daily emails to more than 2000 people at once — i.e., for marketing automation — we recommend using a marketing automation tool. Mixmax is currently optimized for sending individual, personalized messages at scale, directly from Gmail — but not for sending thousands of emails each day.
Mixmax may limit the number of emails that can be sent by a single user in a day to 1000, to ensure users are not rate-limited by Google (we work with Gmail as the underlying email service). You can learn more about Gmail's specific account limits here.
Additional key factors related to rate limiting
Bear in mind that a number of factors will impact the exact number of messages you're able to send. Listed below are a few things that can contribute to your email reputation and how Google treats your account with regards to sending emails in bulk.
- If your bounce rate is high and/or you're sending to malformed or invalid emails you are much more likely to be rate limited.
- If recipients are marking your emails as spam, you are much more likely to be rate limited. Each time a recipient clicks "Mark as spam" in Gmail, Gmail penalizes the sender by reducing their daily send quota.
- Prior sending behavior on your account will impact what the limit is for you. Learn more in Protect your email reputation.
- The rate of sending is just as important as the number of messages sent per day. G Suite customers can send up to 2000 emails per day — but cannot send all these emails at once. Sending must be spaced out over time.
- Making sure your email is configured so that recipient email servers can correctly direct messages is also very important. Google mentions in the bulk sending guidelines that it is important to publish your SPF and DMARC records. Here's how you can check on these settings in Mixmax.
Here are some tips Google shares on their help center to get the best results out of bulk sending...
Google's recommendations for sending bulk email
Here are some ways (direct from Google) to avoid exceeding limits when sending a large amount of mail, such as for a marketing campaign:
- Stagger mass communications over 2 days—Send messages to one group of recipients, wait 24 hours, and then send to another group.
- Review bulk sending guidelines and best practices—Some email recipients might report bulk messages as spam. Therefore, you need to ensure that all recipients are willing to receive the emails. You can also check email settings for any incorrectly configured forwarding rules or filters. For details, see our bulk sending guidelines and best practices.
How many sequence recipients can I send my sequences to?
Mixmax has some safeguards in place to help prevent your account from getting rate limited. You can upload a CSV (or import a list of recipients) with up to 2,000 recipients (please note that Salesforce DOES put a limit of 200 recipients you can import at a time; we recommend breaking down your Salesforce lists accordingly). If you upload a recipient list with more than 500 recipients we'll space out the sending, over multiple weekdays, sending to 500 recipients per day. We send the messages individually, and space them out over time. If you want to send to more than 2,000 recipients, we recommend sending in batches, a few days apart.
Alternatively, you can send from multiple Gmail accounts - just share your sequence with someone on your team.
How will I know if I get rate limited?
Getting rate limited can be very frustrating and in some cases can cause your work to come to a halt. If your account gets rate limited, you will receive a notification from Google in your email. Depending on the rate limiting event, it can last for a few minutes up to 24 hours (or more in extremely rare cases).
Typically with rate limiting events, Google will prevent all emails from being sent from your account. This includes individual messages that you are trying to send outside of any Mixmax sequences or other campaigns you have running. Keep in mind, rate limiting events will prevent all connected services from accessing your email, not only Mixmax.
What happens to my sequences when I get rate limited?
In the case of a rate limiting event where you have active sequence recipients, Mixmax will continue trying to send to those recipients for up to 12 hours from the initial delivery time. In many cases, that is enough time for the rate limit to be lifted and your emails will get sent out, just a little later than originally scheduled.
In the rare event that your account is limited for more than 12 hours, then Mixmax will consider the recipients failed and will send you an email notification letting you know we were unable to send the sequence messages out. In this case, you will need to send the messages again.
How can I resend my sequences after getting rate limited?
After your account is rate-limited, we recommend waiting 24 hours before retrying unsent messages, to make sure your high-volume sending doesn't raise a red flag again. To retry messages, go to the Reports tab for the affected sequence. The email you received from Mixmax includes a link to the specific sequence.
In the reports tab, you should see a red button with an error message indicating some of your messages could not be sent. Click the Resend to x recipients button — see screenshot below:
When you click the button, your emails will start retrying immediately. The send times will be spaced out to minimize the chance of being rate limited again.
If you are unable to locate the button to retry the recipients or have additional questions about being rate limited, feel free to reach out to firstname.lastname@example.org