SMTP2GO has a technical maximum number of recipients per individual email of 400 recipient email addresses.
In general, we recommend sending an email to no more than 50-100 recipients, as problems can arise with email delivery to recipient mail servers, and emails sent to numerous email addresses can often be regarded as being spam.
For accounts created before 2024 and on a Professional plan or above with a dedicated IP address, it's important to note that emails with 50+ recipients will be processed differently for performance optimization and delivered via a shared IP address. To avoid this, please contact support to have your account upgraded to our newer delivery model (it will require being assigned a new dedicated IP address which our team will discuss with you). Otherwise, if you need to ensure an email with multiple recipient addresses is delivered via your dedicated IP address, it must contain less than 50 recipients in total (To, BCC and CC).
The best solution is to use mailing list software when sending emails to hundreds (or thousands) of recipients, which sends each email to only one recipient each.
For example, if your mailing list has 2,000 email addresses, it would send out 2,000 individual emails, with each email being sent to only one recipient.
This approach is the best solution to sending large quantities of emails, as the emails can be personalized (e.g. with an unsubscribe link that is unique to the recipient, or they could be greeted by their name in the email). The emails are also much less likely to be filtered out as spam by the recipients.
For more information, see the mailing list software that we recommend.
If you have questions when sending emails to multiple recipients or any other part of our service, please reach out to our friendly support team for assistance.