How many cold emails can I send per day without hurting my domain?

Why it happens

Mailbox providers track volume and feedback per sending domain and IP. A domain with no history that suddenly sends hundreds of messages looks like the pattern spammers use, so receivers rate-limit it or send it to spam. Reputation is earned by sending steady volumes that people do not complain about.

Volume also compounds with mistakes. Fifty emails to a bad list produce a handful of bounces you can fix. Five hundred produce enough that the domain is flagged before you notice.

The fix that works without GrowFast

1. Start at about 15 a day. Write to the best-fit companies first, those most likely to reply, so early feedback is good.
2. Send at the same time each day. Google recommends a consistent rate and avoiding bursts, especially without a history of large volumes.
3. Raise volume only while results are clean. Google's advice if messages start bouncing or deferring is to reduce volume until errors fall, then increase slowly. Do not double overnight.
4. Count follow-ups in the daily total. A follow-up is an email like any other. A campaign of 15 first emails and 15 follow-ups is 30 a day.
5. Watch Postmaster Tools and your bounce rate. Check spam rate and domain reputation, and bounce rate by address type, every few days at first.
6. Do not spread the same volume over fresh domains to dodge the ramp. Each new domain starts with no reputation. Ten domains each at 15 a day is a pattern receivers also notice.
7. Pause on any complaint spike. Stop sending, find the cause, then resume lower.

Do I need a warm-up tool?

Some tools exchange emails between members' mailboxes to build a sending history. GrowFast does not run such a network and we cannot tell you whether they work or what receivers make of them. What we do is enforce a gradual ramp, so new domains never send a full allowance on day one.

When to use GrowFast

The ramp, the 500-a-day account ceiling, the monthly allowance and the automatic pause are enforced in the sender, so an agent cannot exceed them on cold outreach by asking. Follow-ups are not blocked by the ramp or ceiling, but they use up room that new emails would otherwise have. list_sending_domains returns the account's sending domains and the managed address with the sends remaining today, and get_email_allowance returns the monthly allowance.

When it is not the right tool. If you need thousands of cold emails a day, GrowFast's 500-a-day account ceiling is too low for you; a different sending setup is needed.

Plans and limits are on the pricing page.

Ask your AI assistant

Paste this into an assistant that has the GrowFast MCP server connected. The tools it uses need the full server with an API key.

Assign to GrowFast: show me my sending domains and how many sends each has left today (list_sending_domains) and my monthly allowance (get_email_allowance). Don't send anything. Show me the numbers so I can approve how many emails to queue today.

Tools used: list_sending_domains, get_email_allowance

FAQ

Sources

• Google, Email sender guidelines (Gmail Help) (read 2026-11-13)

Related

• Why do my cold emails land in spam, and how do I fix it?
• Should I send cold email from a separate domain, and how do I set one up?
• How do I check that SPF, DKIM and DMARC are set up before I send cold email?
• All problems and solutions