Why Are My Emails Going to Spam? 9 Causes and Real Fixes

Quick answer: Most emails go to spam for one of three reasons: your domain is not authenticated (SPF, DKIM and DMARC are missing or broken), people are not opening or are marking your emails as spam, or the message itself looks risky. Check authentication first, then clean your list, then fix the content.↗ Share on X

Your emails are most likely going to spam for one of three reasons: your domain is not properly authenticated (SPF, DKIM or DMARC is missing or broken), your readers are ignoring or reporting your emails, or the message itself looks risky to filters. Fix them in that order. Authentication is the fastest win, list cleaning is the biggest win, and content tweaks come last.

Below are the nine causes we see most often, how to spot each one, and exactly what to do.

Which cause is hitting you? A quick diagnosis table

READ ALSOWelcome Email Sequence Setup: 5 Steps and a Copy Schedule →How to Pick Email Marketing Software That Syncs With a CRM →New Email Domain Warm-Up: A 6-Week Schedule to Skip Spam →

Is your domain authenticated with SPF, DKIM and DMARC?

This is the number one cause, and the easiest to check. These three records live in your domain's DNS (the settings panel where you bought your domain, such as your registrar or Cloudflare). They prove to Gmail and Outlook that you are allowed to send email for that domain.

• SPF (Sender Policy Framework): a list of the services allowed to send email for your domain.
• DKIM (DomainKeys Identified Mail): a digital signature added to every email, so the receiver knows it was not changed on the way.
• DMARC: a rule that tells inbox providers what to do when SPF or DKIM fails, and sends you reports.

Since February 2024, Gmail and Yahoo require bulk senders (roughly 5,000 or more messages a day to their users) to have all three, plus a one-click unsubscribe link. Smaller senders still get filtered harder without them.

How to check in two minutes:

1. Send an email from your tool to a personal Gmail address.

2. Open it, click the three dots, and choose Show original.

3. Look for three lines: SPF: PASS, DKIM: PASS, DMARC: PASS.

If any says FAIL or is missing, go to your email tool's help center and search "authenticate domain". Every major tool (Mailchimp, Brevo, ConvertKit, MailerLite and others) gives you the exact records to paste into your DNS. A safe starting DMARC record is:

`v=DMARC1; p=none; rua=mailto:you@yourdomain.com`

The `p=none` part means "just report, don't block anything yet", so it will not break your mail while you test.

Are you sending from a free address like Gmail?

READ ALSOSpam-Safe Email Subject Lines: Rules and a 10-Point Check →Pick Email Marketing Software You Won't Outgrow in a Year →How to Test Email Deliverability Before You Pay for a Tool →

If your "From" address is @gmail.com, @yahoo.com or @hotmail.com but you send through a marketing tool, the email claims to come from Gmail while actually coming from somewhere else. Filters treat that as a red flag, and many tools will rewrite or block it.

Fix: buy a domain (usually a small yearly cost) and send from an address like hello@yourbusiness.com. Then authenticate that domain as shown above.

Did you buy, rent or scrape your email list?

This one quietly destroys deliverability. Purchased lists contain dead addresses, people who never agreed to hear from you, and sometimes spam traps: addresses that exist only to catch senders who don't get permission. Hitting a few can land your whole domain in spam.

What to do:

1. Stop sending to that list completely.

2. Keep only people who signed up themselves, ideally with double opt-in (they confirm by clicking a link in a first email).

3. Add a clear signup form to your site and grow slowly from real visitors.

Are people ignoring or reporting your emails?

Gmail and Outlook watch how readers react. Opens, replies and "not spam" clicks help you. Deletes without opening and "report spam" clicks hurt you. Google advises senders to keep their spam complaint rate below 0.1% and never let it reach 0.3%. You can see your own rate for free in Google Postmaster Tools once you verify your domain.

Common reasons people report you:

• They forgot they signed up (you waited months before the first email).
• You email far more often than you promised.
• The unsubscribe link is hidden, so "report spam" is easier.

Fixes that work:

• Send a welcome email right after signup.
• Tell people how often you'll write, and stick to it.
• Put a visible unsubscribe link at the top or bottom of every email.
• Every few months, remove subscribers who haven't opened anything in a long time (many senders use 90 to 180 days as the cutoff). Send them one "Do you still want these emails?" message first.

Did you suddenly send a lot more email?

Inbox providers get suspicious when a sender who normally sends 200 emails suddenly sends 20,000. This is common with new accounts, new domains and seasonal promotions.

Fix it by warming up: start with your most engaged subscribers, then increase the volume gradually over a couple of weeks. Many tools do this automatically if you turn on "warm-up" or send in batches.

Does your email content look like spam?

Content matters less than reputation, but it can tip a borderline email into spam. Watch for these:

• Subject lines in ALL CAPS or with many "!!!" and "$$$".
• One big image with almost no text. Filters can't read images, so they get suspicious. Aim for more text than images.
• Link shorteners like bit.ly. Spammers use them to hide destinations. Use full links.
• Links to low-quality or blacklisted sites.
• Attachments, especially .zip or .exe files. Link to a file on your site instead.
• Broken HTML from copying and pasting from Word. Build emails in your tool's editor.

A simple rule: write the email as if you were writing to one person you know.

Is your domain or IP on a blocklist?

If you did everything above and still land in spam, check whether your domain or sending IP is on a public blocklist. Free tools such as MXToolbox let you type your domain and see results in seconds.

If you share an IP with other customers of your email tool, another sender may have hurt it. Contact your tool's support; they can move you or investigate. If your own domain is listed, each blocklist site explains how to request removal, usually after you fix the cause.

Is your unsubscribe and footer setup complete?

Laws like CAN-SPAM in the U.S. require a working unsubscribe option and a physical mailing address in marketing emails. Missing these can make filters and readers distrust you. Check that every campaign has:

1. A one-click unsubscribe link that works.

2. Your business name and a valid postal address.

3. A reminder of why they're receiving the email ("You signed up at yourbusiness.com").

A 20-minute checklist to run today

1. Send a test to Gmail and check Show original for SPF, DKIM and DMARC.

2. Add any missing records using your email tool's guide.

3. Confirm your "From" address uses your own domain.

4. Sign up for Google Postmaster Tools and verify your domain.

5. Remove purchased or scraped contacts.

6. Turn on double opt-in for new signups.

7. Replace shortened links with full links in your next email.

Your next step

Right now, send one test email to a personal Gmail account and open Show original. Write down whether SPF, DKIM and DMARC each say PASS. If even one fails, fix that before you send another campaign. It is the single change most likely to move you back to the inbox.

FAQ

How do I check if my emails are going to spam?

Send a test to your own Gmail, Outlook and Yahoo addresses and see which folder it lands in. Then open the message, choose "Show original" in Gmail, and look for SPF, DKIM and DMARC. Each one should say PASS.

Can one word like "free" send my email to spam?

Rarely on its own. Modern filters look at your sender reputation and how readers react far more than single words. But a subject full of capital letters, dollar signs and exclamation marks does add risk, so keep it plain.

How long does it take to fix spam folder problems?

Authentication fixes can start helping as soon as the DNS records spread, often within a day. Repairing a damaged sender reputation takes longer, because inbox providers need to see several weeks of good engagement before they trust you again.