ZapBounce and Streak
Streak runs inside Gmail and sends through your own account. Its mail merge is convenient and it puts your personal sending reputation directly on the line.
Google is not gentle about accounts producing bounces at volume. The consequence reaches your ordinary correspondence rather than the merge alone.
A mail merge from your own Gmail is judged as you
Google evaluates the sending account. A merge to two hundred addresses where thirty bounce looks like an account working through a harvested list, and Google's response is to throttle or filter that account.
That reaches your one-to-one email. A reply to a customer landing in their spam folder is a much worse outcome than a merge underperforming, and it is hard to connect back to the cause.
Gmail also enforces daily sending limits, so bounced addresses spend part of a quota that a Workspace account cannot exceed.
How the data moves
Verify the merge list before the merge
Not the whole CRM, just the addresses about to receive the merge. That is where the risk is concentrated.
Use a Streak column for the verdict
Streak pipelines have custom columns, and a verdict column lets you filter the merge source to confirmed addresses.
Verify through Google Sheets where the list lives there
Streak imports from Sheets, and verifying the sheet before import is a shorter route than verifying inside the CRM.
Keep merge batches small
Gmail's limits are per day and unforgiving. A verified list of two hundred beats an unverified list of five hundred that gets you throttled halfway through.
Setting it up
- Add a column to the Streak pipeline for the verdict and one for the check date.
- Export the boxes you plan to merge to, or verify the source sheet directly.
- Verify the addresses and write the verdicts back into the column.
- Filter the merge source so only confirmed addresses are included.
- Keep each merge inside your Gmail daily limit with room to spare.
- Re-verify any list older than a month before merging to it.
Streak: common questions
Why is this riskier than a marketing platform?
Because the sending identity is your own Gmail account. The damage reaches your personal correspondence, not a campaign metric.
How large can a Streak merge safely be?
Inside your Gmail daily limit with headroom. The exact number depends on your Workspace plan and is worth checking rather than assuming.
Should I verify the whole pipeline?
Only the merge list. That is where the sending happens and where the risk sits.
Check a Streak export today
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