AWS SES: SendBulkEmail API recipients limit and maximum send rate

You're correct that there is a limit on the number of recipients for bulk email operations in Amazon SES, but let's clarify a few points:

1. The SendBulkTemplatedEmail API operation does indeed have a limit of 50 destinations (recipients) per request. This is specific to the bulk email API and is different from the regular SendEmail API.

2. Regarding how this fits with the maximum send rate, it's important to understand that sending quotas in Amazon SES are based on recipients, not messages. Each recipient counts individually towards your quota, even when sent in a bulk operation.

For example, if you send a bulk email to 50 recipients, it counts as 50 emails against your quota, not as one. So, if your maximum send rate is 14 emails per second, you would need to manage your sending to stay within this limit.

To illustrate:

• If you send a bulk email to 50 recipients, it would use up about 3.57 seconds of your quota (50 recipients / 14 per second).
• You would then need to wait before sending the next batch to avoid exceeding your rate limit.

It's crucial to implement a system that spaces out your bulk email sends to comply with your account's maximum send rate. This might involve adding delays between bulk sends or breaking larger lists into smaller batches.

Remember that these limits are in place to maintain a good sending reputation and prevent sudden spikes in email volume that could be flagged as spam by email providers. If you need to send at higher volumes or rates, you can request an increase in your sending quotas through the AWS Support Center.
Sources
Managing your Amazon SES sending limits - Amazon Simple Email Service
Managing your Amazon SES sending quotas - Amazon Simple Email Service
Amazon SES and deliverability - Amazon Simple Email Service