Sending hours, the hourly limit and the gap between emails
Send only in working hours, cap how many go out per hour, and add a random pause between emails so a campaign looks like a person, not a machine.
Sending hours (per campaign)
On the Schedule step, or later under Hours and rules on the campaign's page, tick Send only in working hours and pick the days, the times and the time zone. Outside those hours the campaign's emails wait and start again when the hours open. Nothing is lost or skipped.
Example
Monday to Friday, 09:00 to 17:00, Europe/Bucharest. You press Send on Friday at 18:30: nothing goes out until Monday at 09:00, then the emails go out through the day.
Pick your recipients' time zone, not yours, if they are elsewhere. Working-day follow-ups count Monday to Friday in the same zone.
Hourly limit and the gap (per mailbox)
On the Mailboxes page, under Sending limits, you can add a per hour limit and a gap between emails: a shortest and a longest number of seconds. After each email the mailbox waits a random time between the two before sending the next one.
Example
A gap of 60 to 180 seconds means about 30 emails an hour. A 120-person campaign then takes around four hours of sending time, spread out like a person working through a list.
| Setting | Where | What it does |
|---|---|---|
| Per day | Mailbox | The most this mailbox sends in a day (lower while it warms up). |
| Per hour | Mailbox | The most it sends in any hour. |
| Per minute / second | Mailbox | Short bursts; match your provider's own limits. |
| Gap | Mailbox | A random wait between two emails from this mailbox. |
| Sending pace | Campaign | Slow, balanced or fast. The stricter of pace and the mailbox's limits wins. |
| Sending hours | Campaign | Days and times the campaign may send. |
If it seems slow
- It is outside the campaign's sending hours: the run page shows emails as waiting, and they go when the hours open.
- The mailbox reached its hourly or daily limit: the rest wait for the next hour or the next day (days are counted in UTC).
- A long gap ends the mailbox's turn: the next email goes when the gap is over, within a minute of it.
- The campaign is paused, or the mailbox's login is failing: both show a notice on the campaign and on the Mailboxes page.
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