Why Are My Emails Going to Spam? Troubleshooting Email Deliverability

Why Are My Emails Going to Spam?

If your emails are landing in spam folders instead of inboxes, there are a handful of common causes. Most of them come down to missing or misconfigured DNS records, a poor sending reputation, or content that triggers spam filters. This guide walks through each one so you can find and fix the problem.

Step 1: Check Your DNS Records

Missing or incorrect DNS records are the most common reason emails go to spam. You need three records set up correctly: SPF, DKIM, and DMARC.

SPF Record

SPF tells receiving servers which mail servers are authorized to send email for your domain. If your SPF record is missing or does not include Mailbux, your emails may be marked as spam or rejected.

Your SPF record should be:

v=spf1 include:msg25.com ~all

Check yours now: SPF Lookup Tool

DKIM Record

DKIM adds a cryptographic signature to your emails. Without it, receiving servers cannot verify that your emails actually came from you, which hurts deliverability.

To enable DKIM in Mailbux: go to your Domains page, open the domain menu, click Enable DKIM, then click View DNS Records and add the DKIM TXT record to your DNS provider.

Verify your DKIM is working: DKIM Lookup Tool

DMARC Record

DMARC tells receiving servers what to do when an email fails SPF or DKIM. Without DMARC, many mail providers treat your domain as less trustworthy.

A basic DMARC record looks like this:

v=DMARC1; p=quarantine; rua=mailto:dmarc@yourdomain.com; pct=100

Add it as a TXT record with the host _dmarc.

Step 2: Check If Your IP Is Blacklisted

If your sending IP address appears on a spam blacklist, your emails will go to spam or be rejected outright. This can happen if a previous user of the same IP sent spam, or if your account was compromised.

Run a blacklist check: Blacklist Check Tool

If you find your IP is listed, contact Mailbux support for assistance with delisting.

Step 3: Check Your Email Content

Spam filters also analyze the content of your emails. Common content issues include:

Spammy subject lines: Avoid all-caps, excessive exclamation marks, or phrases like "FREE!!!" or "Act now".
Too many links: Emails with many links, especially to unfamiliar domains, score higher on spam filters.
Image-only emails: Emails with no text content and only images are often flagged as spam.
Missing unsubscribe link: For bulk or marketing emails, a missing unsubscribe link can trigger spam filters and violates CAN-SPAM rules.
Mismatched From address: The From address should match the domain you are sending from.

Step 4: Check Your Sending Reputation

Even with correct DNS records, a poor sending reputation can hurt deliverability. This builds up over time based on bounce rates, spam complaints, and engagement.

Keep your bounce rate low by removing invalid addresses from your list.
Avoid sending to people who have not opted in.
Monitor spam complaint rates — anything above 0.1% is a problem.

Troubleshooting Checklist

Verify SPF record includes msg25.com using the SPF Lookup Tool
Verify DKIM is enabled and published using the DKIM Lookup Tool
Add a DMARC record if you do not have one
Check your IP against blacklists using the Blacklist Check Tool
Review your email content for spam triggers
Test your outgoing mail server with the SMTP Test Tool
Check your MX record is correct using the MX Lookup Tool

Still Having Issues?

If you have checked everything above and emails are still going to spam, contact Mailbux support with the full email headers from a message that was flagged. Headers contain detailed routing information that helps diagnose the exact cause.