Why your business emails go to spam

Business emails go to spam for a handful of reasons: your domain is missing the records that prove the mail is really from you, you are sending through a server your domain does not list, the message itself looks like junk, or your address has picked up a poor reputation. The first one is by far the easiest to fix and the most common for small businesses. Below is how to find out which problem you have, starting with a check you can do in two minutes.

First, find out what the receiving side thinks of you

Before changing anything, look at one of your own emails through the eyes of a big mail service.

1. From your business address, send a short, normal message to a personal Gmail account.
2. Open it in Gmail on a computer. Click the three dots next to the reply arrow and choose Show original.
3. At the top you will see three lines: SPF, DKIM and DMARC, each with PASS, FAIL or NONE.

What the results tell you:

• All three PASS: your setup is fine. The problem is more likely the content, the way you send, or reputation. Skip to those sections below.
• SPF FAIL or NONE: your domain does not list the server that sent this message as allowed.
• DKIM FAIL or NONE: your messages are not being signed, or the signature record is missing.
• DMARC FAIL or NONE: there is no DMARC record, or the other two checks did not line up with your domain.

Do the same test with an Outlook.com or Yahoo address if your customers use those. Results can differ.

Reason 1: The proof-of-identity records are missing

Anyone can type any From address on an email, so mail services check whether your domain vouches for the message. That is the job of three records in your DNS (your domain's settings list): SPF says which servers may send for you, DKIM adds a signature, and DMARC says what to do when the checks fail. Since early 2024, Gmail and Yahoo have required senders to have at least some of this in place, and they are stricter with businesses that send a lot of mail.

If your test shows NONE anywhere, ask your email provider for the exact records and add them where your domain's DNS is managed. The plain explanation of each, and the common mistakes like having two SPF records, is in SPF, DKIM and DMARC for small business owners.

Reason 2: You send through something your domain does not know about

This is the most common hidden cause. Your mailbox might pass every check, but other tools also send mail with your address on it:

• Invoicing and estimating software
• Booking and appointment reminders
• Your website's contact form confirmations
• Newsletter tools
• Gmail's Send mail as, routed through Gmail's servers

Each of these sends from its own servers. If your SPF record does not include them, and they are not set up to sign with your domain's DKIM, receivers treat those messages as possible forgeries. Look at the settings page of each tool for something like "custom sending domain" or "authenticate your domain". It gives you records to add.

A related trap: website contact forms that send an email from the customer's address to you. Your mail server is claiming to be the customer's Gmail, which fails every check. A properly built form sends from your own domain and puts the customer's address in the Reply-To field. If enquiries from your site keep landing in spam, making sure nothing from your contact form gets lost covers how to test it.

Reason 3: The message looks like junk

Filters read the message as well as the envelope. Things that hurt ordinary business mail:

• A message that is mostly one image, like a flyer pasted in with little text.
• Link shorteners and links whose visible text says one address but goes to another.
• Large or unusual attachments, especially zipped files. Send big photos as a shared link instead.
• All-caps subject lines and words like FREE or URGENT in the subject.
• A signature stuffed with ten social icons and tracking links.
• No plain text at all, just a designed template.

A plain, short email with your name, a clear subject like "Estimate for your kitchen sink repair" and one attached PDF is what gets through most reliably.

Reason 4: How you send

• Many recipients in BCC. Sending a holiday note to two hundred customers from your normal mailbox looks like spam to filters, and Gmail and Yahoo expect bulk senders to include an easy unsubscribe link. Use a proper newsletter tool, authenticated with your domain.
• A sudden burst from a new address. A brand-new domain that sends a lot of mail in its first week looks suspicious. Start with normal day-to-day messages.
• Sending to old lists. Emailing addresses that no longer exist produces bounces, and bounces damage your reputation quickly.

Reason 5: Reputation

Mail services remember how people react to mail from your domain and from the server it comes through. If recipients often mark your messages as spam, future mail suffers. If you are on shared hosting email, another customer on the same server may have caused trouble, and your mail pays for it.

Signs of a reputation problem: your test shows SPF, DKIM and DMARC all passing, your messages are plain and personal, and they still land in spam. Your email provider's support can usually tell you whether their server is on a block list. Moving to a larger mailbox provider often solves it, and the address stays the same. Google publishes its sender guidelines at support.google.com.

What to do this week

1. Send yourself a test at Gmail and read Show original.
2. Fix any NONE or FAIL with records from your email provider.
3. List every tool that sends mail as your business and authenticate each one.
4. Test your website's contact form and check where the enquiry lands.
5. Strip one-image emails and shortened links from anything you send customers.
6. Ask new customers to reply to your first message.

Spam problems often show up first on enquiries from the website. If your current site's form is old and nobody is sure how it sends, you can see your site rebuilt first with a form you can test against your own inbox.