Mixmax vs. GMass:  big mail merges, or follow-ups for the people you know

Yes. GMass auto follow-ups can be set to send only to people who didn't reply, so once someone replies, their pending follow-ups don't send. You can also stop them on opens or clicks, or stop everyone at a company once one person replies.

Mixmax works the same way: follow-ups send as replies in the same thread and stop when the person replies.

GMass is strong at mail merge from Gmail. It sends to large lists, reads live data from Google Sheets, supports unlimited follow-up stages, and has A/B testing and inbox rotation on higher plans. It can also send through its own sending servers when you need to go past Gmail's daily limits.

If you send one email to hundreds or thousands of people at once, it's built for that.

Usually, yes, on paid plans. GMass Standard is $20.75 a month billed yearly ($29.95 monthly), per its January 2026 pricing update. Mixmax starts at $29 per user a month billed yearly ($34 monthly).

The difference is that Mixmax has a free plan, and it covers more than sending: reminders, booking links and Salesforce and HubSpot sync.

Yes. You can add follow-ups to a single email while you write it. If they don't reply, Mixmax sends your follow-up from your Gmail. If they do, it stops.

Choose GMass if your main job is sending one email to a big list from Gmail, and you want fine control over sending limits and testing.

Choose Mixmax if you follow up with people you actually know, a few at a time or a whole list, and want each follow-up to land in the same thread and stop when they reply. Our guides on how to follow up after no response and on automated email follow-up tools cover both approaches.