Use a subdomain for marketing emails

What it means

Mailbox providers like Gmail and Outlook give each sending domain a reputation, based on how people react to its emails. Newsletters and promotions get more spam reports and less engagement than personal emails. If both use the same domain, a bad campaign can push your invoices, quotes and replies to customers into spam.

A common solution is to send marketing from a subdomain, for example:

• yourdomain.com for people's mailboxes and business emails;
• news.yourdomain.com or mail.yourdomain.com for newsletters;
• optionally notify.yourdomain.com for automatic emails (orders, password resets).

Subscribers still see your brand, but receivers can track each stream separately.

Why it matters

• Problems with a campaign hurt the subdomain's reputation more than your main domain's.
• Each tool gets its own SPF record, which keeps your main SPF short and under the 10 lookup limit.
• DMARC reports are easier to read, because each stream has its own name.

A subdomain is not a hiding place: providers still connect it to your main domain. It separates reputations, it does not erase bad habits.

How to check

• Send a test email from your newsletter tool to a Delivmail test address from the home page (/). The report shows the From domain and whether SPF, DKIM and DMARC pass for it.
• Use the Domain scanner: type the subdomain at /domain-scanner to check its records.

How to fix it

1. Pick the subdomain. Something clear like news.yourdomain.com. Avoid look-alike domains such as yourdomain-mail.com: they look like phishing and start with no reputation at all.
2. Add it in your email tool as a sending domain, and add the DKIM records it gives you, for example s1._domainkey.news.yourdomain.com.
3. Set up SPF for the subdomain if the tool asks for it. It is a separate TXT record on news:

   v=spf1 include:spf.newsletter-example.com ~all

4. Set up the custom return path (bounce domain) under the same subdomain if the tool offers it, so SPF aligns too.
5. DMARC: your main _dmarc.yourdomain.com record covers subdomains by default (or with the sp= tag). You can also publish a specific one at _dmarc.news.yourdomain.com.
6. Add an MX record or a working reply address if people may reply to the newsletter, so replies are not lost.
7. Change the From address to something like hello@news.yourdomain.com.
8. Warm it up. A new subdomain has little history. Start with your most engaged readers and grow the volume over a few weeks.

Check that it is fixed

Send a campaign to a new Delivmail test address: SPF, DKIM and DMARC should all pass for news.yourdomain.com. Then send a normal email from your mailbox and confirm it still passes for your main domain. With Delivmail DMARC monitoring in the paid dashboard, you can follow both streams in the daily reports.