MergelineCan I mail merge with Google Apps Script instead of an add-on?
Updated October 29, 2026
Yes. Apps Script can read each row of a Google Sheet and send a Gmail message for it, at no cost and with no third-party access to your account. You pay in time: you copy or write the script, approve its permissions, and fix it when it breaks. Formatting, links, follow-ups and reply checks are all extra work you build yourself.
What a script does well
- One-off jobs with a tidy sheet and a plain text email.
- Unusual needs, like attaching a different Drive file per row.
- Keeping everything inside your own Google account.
Video walkthroughs show how to build one step by step, so you do not have to start from a blank file.
Where it gets hard
- Formatting. Developers on Reddit note that getting links and rich text right in a script-based merge takes extra work.
- Pacing. A loop sends as fast as it can unless you add delays and batches yourself.
- Follow-ups and replies. You would need to store thread IDs, check for replies and trigger new sends on a timer.
- Gmail’s limits still apply: 500 a day on a standard account and 2,000 on Workspace.
Script, add-on or extension?
| Apps Script | Mergeline | |
|---|---|---|
| Cost | Free | Free for 60 a day, Pro $12 a month |
| Setup | Code and permissions | Install and import a list |
| Preview each email | Build it | Built in |
| Follow-ups that stop on reply | Build it | Up to 7 with Pro |
| Where your data lives | Your Google account | Your browser |
If you enjoy code and send rarely, a script is a fine choice. If you send every week, the time adds up quickly.
Safety notes for scripts
- Test with a sheet that holds only your own address first.
- Add a column the script fills with “sent”, so a rerun does not email people twice.
- Read the permission screen. A script you copied asks for access to your Gmail like any app.
Read the full guide: Mail merge from Google Sheets
Related answers
Sources
- YouTube: mail merge with Apps Script
- r/GMail: improving Google’s mail merge script
- Google: Gmail sending limits
- Google Workspace: Gmail sending limits
Facts checked October 29, 2026. Google and other vendors change their limits and prices, so check the source before you rely on a number.
Mergeline does this from your own Gmail. Free for 60 emails a day with merge tags and no branding. Pro is $12 a month or $99 a year for follow-ups, scheduling and attachments.