Gmail 550 5.4.5: “Daily user sending limit exceeded”

Short answer: Your own Gmail or Google Workspace account hit its daily sending limit, so Google stopped sending for you; no recipient blocked you. Sending resumes within 24 hours. For newsletters or other bulk mail, use a sending service instead of a mailbox.

The bounce looks like this
550 5.4.5 Daily user sending limit exceeded. For more information on Gmail sending limits, go to …
550 5.4.5 Daily user sending quota exceeded. … - gsmtp
You have reached a limit for sending mail.
550 5.4.5 Daily SMTP relay limit exceeded for user.

What it means

The block is on your own account: once it passes a daily limit, Google stops it from sending for up to 24 hours, counted over a rolling 24 hours. Personal Gmail: about 500 emails a day, or 500 recipients in one message. Google Workspace: 2,000 messages a day per user (500 on trial accounts, 1,500 with mail merge), 10,000 recipients a day in total, 2,000 different external recipients a day, and 100 recipients per message when an app sends over SMTP. Every To, Cc and Bcc address counts, and so does mail sent from aliases, by delegates or by the vacation responder. Google notes the limits can change without notice. The SMTP relay lines refer to the separate limit of Workspace's smtp-relay service.

How to fix it

  1. Wait: sending comes back by itself within 24 hours (Google says 1 to 24 hours for personal Gmail). You can still receive mail meanwhile.
  2. Pause scripts, mail merges and apps that send through the account until the limit resets. Then spread the remaining mail over several days.
  3. Count what you really send: a message to 50 people uses 50 of the recipient limit, and aliases, delegates and auto-replies share the same limit.
  4. Workspace trial? Trial accounts keep the lower limits until the domain has paid at least US$100 in total, which can take up to 75 days.
  5. For newsletters, announcements or app notifications, use a sending service instead of a mailbox, for example Amazon SES, Postmark or Brevo. For a small group of people, Google suggests a Google Group.
  6. When you move bulk mail to a service, add it to SPF (SPF generator) and turn on its DKIM with your domain, or Gmail recipients will reject it with 5.7.26 instead.
  7. SMTP relay variant: your Workspace admin can see the relay's sending limits in the SMTP relay service settings.

Check your domain now

After the fix, send a test email to see SPF, DKIM and DMARC pass on a real message, then keep an eye on it: free DMARC monitoring shows every service that sends mail as your domain and which ones fail, in plain English.

Rather not touch DNS? I set up SPF, DKIM and DMARC without breaking your other senders, with a before/after report.

Get it fixed on Fiverr

Prefer to do it yourself? Get the step-by-step Fix Kit ($15) – 28-page guide, checklist, 20+ providers.

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