How many cold emails can you send per day?

Each provider publishes a hard cap. Going over it gets the account temporarily blocked from sending.

• Free Gmail account: 500 messages a day.
• Google Workspace: 2,000 messages a day per user (lower on trial accounts).
• Microsoft 365 (Exchange Online): 10,000 recipients a day per mailbox, and 30 messages a minute.

These limits exist to stop abuse, not to tell you what's safe for cold email. Mail from a mailbox sending hundreds of unsolicited messages a day looks like spam to filters long before it hits the cap.

Common practice is roughly 20 to 50 cold emails per mailbox per day, follow-ups included, with many teams staying near the bottom of that range. Lower volume per mailbox keeps each mailbox's reputation steady and makes problems easier to contain.

• New mailboxes start lower, around 5 to 10 a day, and ramp up over two to four weeks while warmup builds their reputation.
• Spread sends across working hours instead of sending in bursts, and set an hourly limit.
• Follow-ups count towards the daily total, not on top of it.

Divide the emails you want to send per day by a safe volume per mailbox. For example, 600 emails a day at 30 per mailbox needs 20 mailboxes. Spread those over several sending domains (often 2 to 3 mailboxes per domain) so one domain's reputation doesn't carry your whole volume.

mailboxes needed = emails per day / emails per mailbox per day
example: 600 / 30 = 20 mailboxes, across about 7 to 10 domains

Polimatiq's plans are sized this way. Starter allows 3,000 emails a month across 5 mailboxes, which is about 27 per mailbox per working day.

• Bounce rate above about 2%: clean or verify your list before sending more.
• Spam complaint rate approaching 0.3%, the threshold Gmail publishes for bulk senders; keep it well below 0.1%.
• Open or reply rates dropping suddenly on one mailbox or domain while others hold steady.
• Warmup emails starting to land in spam.

When you see these, lower the daily volume on the affected mailboxes and fix the cause before adding more sending capacity.

Set a daily and hourly limit on every mailbox, give each campaign a sending window, and keep warmup running alongside campaigns. In Polimatiq, each mailbox has its own daily and hourly limit, campaigns send within the window you set, warmup is included on every plan, and mailbox health is scored on warmup and bounce rate so you can see which mailbox needs attention.