{"id":94991,"date":"2026-09-25T09:22:40","date_gmt":"2026-09-25T09:22:40","guid":{"rendered":"https:\/\/mailrelay.com\/?post_type=glossary&p=94991"},"modified":"2026-09-25T09:23:40","modified_gmt":"2026-09-25T09:23:40","slug":"sending-domain","status":"publish","type":"glossary","link":"https:\/\/mailrelay.com\/en\/glossary\/sending-domain\/","title":{"rendered":"Sending domain"},"content":{"rendered":"\n

When someone receives your newsletter, the first thing they see is who sent it. If it says hello@yourcompany.com, they recognise your brand. If it says yourcompany2024@gmail.com, they hesitate. And spam filters hesitate even more. Behind that address sits a technical piece that decides much of your deliverability: the sending domain.<\/p>\n\n\n\n

What is a sending domain?<\/h2>\n\n\n\n

A sending domain is the domain your emails are sent from. It’s the part after the @ in the sender’s address: in hello@yourcompany.com, the sending domain is yourcompany.com.<\/p>\n\n\n\n

But an email carries more than one domain inside it. Besides the one the reader sees in the \u201cFrom\u201d field, two others work in the background. The return path<\/a> collects bounces. And the DKIM signature shows which domain takes responsibility for the message. Many platforms add a fourth: the tracking domain, used in links and images.<\/p>\n\n\n\n

For Gmail, Outlook or Yahoo to trust you, those domains have to be authorised and, above all, aligned with the sender’s domain. That’s what DMARC checks.<\/p>\n\n\n\n

Send from your own domain from day one<\/p>

With Mailrelay you authenticate your domain with SPF, DKIM and DMARC, and our support team helps you set it up. Up to 80,000 emails a month for free.<\/p>Create a free account<\/a><\/div>\n\n\n\n

Why you shouldn’t send campaigns from @gmail.com<\/h2>\n\n\n\n

It’s tempting to use the free address you already have. But since 1 February 2024, gmail.com has published a DMARC quarantine policy. Yahoo goes further and has applied a reject policy to its own domain for years.<\/p>\n\n\n\n

What does that mean in practice? Your email marketing platform can’t sign messages on behalf of gmail.com, and it isn’t one of Google’s authorised servers. So if you send a campaign from a @gmail.com address through another tool, the message fails DMARC. It will most likely land in spam or not arrive at all.<\/p>\n\n\n\n

On top of that, Gmail requires every sender to authenticate their domain with SPF or DKIM. Anyone sending more than 5,000 emails a day must use SPF, DKIM and DMARC with alignment. All of that is only possible with a sending domain of your own.<\/p>\n\n\n\n

Main domain or subdomain?<\/h2>\n\n\n\n

Your sending domain can be your main domain or a subdomain, such as news.yourcompany.com or mail.yourcompany.com. Many companies prefer a subdomain for marketing.<\/p>\n\n\n\n

The reason is domain reputation<\/a>. Mailbox providers look at each domain’s history. If a campaign gets lots of complaints, a separate subdomain protects your corporate email: invoices, support or messages from your sales team.<\/p>\n\n\n\n

That said, don’t multiply domains without a reason. Separating types of email makes sense; switching domains to dodge filters doesn’t. We cover this in our entry on sending domain rotation<\/a>.<\/p>\n\n\n\n

The DNS records for your sending domain<\/h2>\n\n\n\n

You set everything up in your domain’s DNS. It’s the system that translates names into addresses and stores each domain’s public information. These are the records you need:<\/p>\n\n\n\n

\"DNS<\/figure>\n\n\n\n