BETA

Bounce Decoder: 554

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

🔧 Related Tools

ANALYSIS TOOLS
🔒 Full Checker Complete email deliverability scan: SPF, DKIM, DMARC, MX, blacklists & more. 📨 SPF Check and visualise your SPF record including the full DNS lookup tree. 🔑 DKIM Scan all known DKIM selectors and validate key strength for your domain. 📧 Email Headers Analyse raw email headers to trace delivery path and authentication results. 📬 Bounce Decoder Decode NDR bounce messages and SMTP error codes to diagnose delivery failures. 🦁 BIMI Verify your BIMI logo record and VMC certificate status. 🔐 DNSSEC Validate the DNSSEC chain of trust: DS, DNSKEY, and RRSIG records. 🔒 MTA-STS Check your MTA-STS DNS record and TLS policy file for enforced encryption. 📋 TLS-RPT Validate your TLS-RPT reporting address for email transport encryption reports. 🌍 WHOIS Look up domain registration details via RDAP.
DIAGNOSTIC TOOLS
🚫 Blacklist / RBL Check IPs and domains against major email blacklists and RBLs. 🌐 DNS Propagation Check DNS record propagation across multiple global resolvers simultaneously.
BUILDER TOOLS
✅ DMARC Builder Build a DMARC TXT record with the right policy, RUA/RUF and subdomain options. 🛠 SPF Builder Generate a validated SPF record by selecting your email senders. 📝 Route 53 Splitter Split long DKIM or SPF TXT records for AWS Route 53's 255-character limit.

554 — Transaction Failed

The 554 SMTP error means the transaction was permanently rejected — often due to spam, a blocklist, or a policy violation. Learn how to investigate.

🔴
Permanent Failure (Hard Bounce)
SMTP Code
554
Category
Transaction Failed
Frequency
Common

💬 What This Error Means

The receiving server refused the message outright with a permanent catch-all rejection. This can mean spam detection, blocklist listing, or a general policy violation.

Common Causes

  • Message content flagged as spam
  • Sending IP or domain on a blocklist
  • Policy-based rejection at the server level

How to Fix This

  • Check if your sending IP is blacklisted with our Blacklist Checker
  • Review email content for spam triggers
  • Verify your authentication setup with our Domain Checker

📋 Real-World Example Messages

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

554 Transaction failed
554 5.7.1 Message rejected as spam by Content Filtering

🔗 Related Error Codes

550 5.7.1
Message Rejected by Policy
550 5.7.0
Message Rejected (Policy)

📚 Official Documentation

↗ RFC 5321 — SMTP

🔧 This Bounce Is Related to Email Authentication

Fixing this type of bounce requires correctly configured SPF, DKIM, and DMARC records. Our free Domain Checker analyses all three in one scan and tells you exactly what to fix.

Run a Free Domain Authentication Check →
🔍

Got a bounce message to decode?

Paste your full NDR email, SMTP error line, or mail log fragment to get an instant plain-English diagnosis.

Open the Bounce Decoder →