Mailbox provider

Outlook.com sending limits

Outlook.com / Hotmail (free)

Account / daily limit~300 recipients per day (Microsoft does not publish an exact figure for free accounts). Brand-new accounts are throttled even lower until they build credibility.
Send rate~20 messages per minute on free accounts; enforced on a rolling 24h window.
Recipients per email100 recipients per message.

The account cap is not a cold-email volume

Like free Gmail, a free Outlook.com/Hotmail address can't send from an authenticated custom domain, so it is not viable for cold outreach regardless of the ~300/day number. Effective inbox-safe cold volume is near zero; if used personally at all, keep it under ~20-30/day.

Good to know

  • Free-account limits are deliberately undisclosed and vary by account age/reputation.
  • New accounts get a low temporary quota that rises only as the account proves legitimate.
  • Rolling-window enforcement: hitting the cap at 2pm unlocks at 2pm next day, not midnight.

Scale safely past one inbox.

Real cold-email scale comes from many inboxes each sending a safe volume, not one inbox maxing its cap. Scheduler Zero spreads sending across warmed inboxes and paces it for you.

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