Why is Gmail blocking my emails?
Gmail blocks emails for several reasons — spam filters, authentication failures, or sending limits. Here's how to diagnose and fix the most common causes.
2 min read · Updated 2026-04-14
General information only. This article may include AI-assisted content. While we aim for accuracy, verify important details before acting on them.
Short answer
Gmail blocks emails because of spam filter triggers, failed email authentication (SPF, DKIM, DMARC), hitting sending limits, or your sending IP/domain being on a blocklist. The fix depends on which of these is causing it.
Most common reasons Gmail blocks emails
1. Spam filter triggers
Gmail's spam filter looks at content, not just sender reputation. Emails get blocked if they:
- Contain too many links
- Use spam trigger words ("FREE!!!", "Act now", "Guaranteed")
- Have mismatched sender name and email address
- Come from a new domain with no sending history
2. Authentication failures (most common for bulk senders)
If you're sending from a domain (not a personal Gmail), Gmail checks three records:
- SPF — verifies your sending server is authorized
- DKIM — cryptographically signs your email
- DMARC — tells Gmail what to do if SPF/DKIM fails
Missing or misconfigured DNS records cause legitimate emails to land in spam or get rejected.
3. Sending limits exceeded
Free Gmail accounts can send ~500 emails/day. Google Workspace allows ~2,000/day. Exceeding these limits temporarily blocks sending.
4. Your IP or domain is blacklisted
Check if your domain or sending IP appears on a blocklist at mxtoolbox.com/blacklists. This happens if someone else on a shared server sent spam.
How to fix it
For personal Gmail:
- Check your Sent folder — did the email actually send?
- Ask the recipient to check their spam folder
- Avoid spam-trigger words in subject lines
- Don't send the same email to many people at once
For business/domain email:
- Use Google's Postmaster Tools (postmaster.google.com) to see your domain reputation
- Set up SPF, DKIM, and DMARC records in your DNS — your email provider (Mailchimp, SendGrid, etc.) will give you the exact records
- Use an email warm-up service if your domain is new
For bulk sending:
- Switch to a dedicated email service (Mailchimp, Resend, SendGrid) — they handle authentication and reputation for you
Common mistakes
- Buying a domain and immediately sending hundreds of emails — Gmail sees new domains with no history as high-risk
- Using a free Gmail account for business newsletters
- Ignoring bounce notifications