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Bounce Decoder: 552 5.2.2

SPF, DKIM, DMARC, FCrDNS, Blacklists & Inbox Prediction

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552 5.2.2 — Mailbox Over Quota

The 552 5.2.2 SMTP error means the recipient's mailbox is full. Learn when to retry, when to remove the address, and what Google and Microsoft return.

🔴
Permanent Failure (Hard Bounce)
SMTP Code
552
Enhanced Code
5.2.2
Category
Mailbox Over Quota
Frequency
Very Common

🔢 Enhanced Status Code Breakdown: 5.2.2

Component Value Meaning
Class 5 Permanent failure
Subject 2 Mailbox status
Detail 2 Mailbox Over Quota

Per RFC 3463 Enhanced Mail System Status Codes. Class (X) = severity, Subject (Y) = category, Detail (Z) = specific condition.

💬 What This Error Means

The recipient's mailbox has exceeded its storage quota. While this is technically a permanent bounce code, the condition may resolve once the recipient clears their inbox.

Common Causes

  • The recipient hasn't cleared old emails and hit their storage limit
  • Low quota on the recipient mail account

How to Fix This

  • Wait a few days and retry — the recipient may free up space
  • Try contacting them through another channel to let them know
  • If this persists for weeks, treat the address as inactive

🏢 Provider-Specific Variations

Google Workspace / Gmail

Google returns 452 4.2.2 (temporary) rather than 552 5.2.2 for quota issues, allowing retries.

📖 Google Workspace / Gmail documentation →

📋 Real-World Example Messages

These are real bounce message formats you might receive. Paste yours into the Bounce Decoder for instant analysis. 

552 5.2.2 Mailbox full
452 4.2.2 The email account that you tried to reach is over quota

🔗 Related Error Codes

452 4.2.2
Mailbox Full (Temporary)
550 5.2.1
Mailbox Disabled

📚 Official Documentation

↗ Google Workspace SMTP errors
🔍

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