- 1
Connectors → open a mailbox → Details tab
Click a connected email account and stay on the Details tab; scroll to Sending Configuration.
- 2
Understand Daily Limit
This is how many emails the mailbox may send per day — a range of 20–500, default 50. New or cold mailboxes should start low.
- 3
Decide: auto-adjust or fixed
With Auto-adjust on (the default), FirstSales manages the daily limit nightly from yesterday's Sending health, and the number is read-only. Turn it off to type a fixed limit and click Save.
- 4
Set a Send ceiling (optional)
Enter a Send ceiling to cap daily sends — auto-adjust still ramps underneath it but never exceeds it. Leave it blank for no cap. Click Save.
- 5
Read the Sending health bar
The 0–100% Sending health score is computed nightly from the prior day's metrics and drives auto-adjust. A low score means the limit gets pulled back automatically.
- 6
Check the last auto-adjust
When present, the info popover next to Sending health shows when the limit was last changed and why (tier and reason).
- 7
Repeat per mailbox
These settings are per mailbox — set them on every sending account, keeping cold ones conservative and aged ones higher.
- 8
Rotate, don't overload
To send more total volume, add mailboxes to the campaign's sender pool rather than pushing one mailbox past a safe limit — see the safe-scaling tutorial.
Pro tips
Hard-won shortcuts that keep warm-up on track.
Leave auto-adjust on and add a ceiling
The safest setup for most users: auto-adjust ramps volume with health, and a Send ceiling stops it climbing past a number you're comfortable with.
Fixed limits are for known-good, aged mailboxes
Turn auto-adjust off only when you have a mailbox with a stable reputation and a volume you already trust.
Watch the health score after warm-up
A dip in the nightly Sending health score is your early warning; auto-adjust will throttle before deliverability tanks — don't override it back up.
More volume = more mailboxes
500/day is the per-mailbox ceiling. Scale by rotating across several senders in the campaign, not by fighting one mailbox's limit.
Frequently asked questions
Where do I set a mailbox's daily limit?
Connectors → open the mailbox → Details tab → Sending Configuration.
What's the range and default?
20 to 500 emails per day, default 50.
What does Auto-adjust do?
It sets the daily limit nightly based on yesterday's Sending health; while it's on, the limit field is read-only.
What is the Send ceiling?
An optional hard cap. Auto-adjust ramps underneath it but never goes above it; leave it blank for no cap.
How is Sending health scored?
Nightly, from the previous day's sending metrics; it drives every auto-adjust decision.
Can I set a limit per campaign instead?
No — the limit is per mailbox. Campaign-level volume comes from how many mailboxes you assign as senders.
Should I raise the limit right after warm-up?
Let auto-adjust do it. A manual jump risks a spam spike; the nightly ramp is safer.
Why did my daily limit change on its own?
Auto-adjust changed it based on Sending health; the info popover shows the exact time and reason.
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