You can use a NameUK domain with Microsoft 365 email by verifying the domain and publishing the records supplied by Microsoft. Prepare the users and mailboxes before changing MX routing. Keep your website records in place. Your domain registration stays with NameUK; Microsoft 365 supplies the email subscription and mailbox service.
Before you begin
- A Microsoft 365 organisation with an email-capable subscription and suitable administrator access.
- A list of every mailbox, shared address and alias currently using the domain.
- Access to the active DNS host and a copy of the existing records.
- A migration plan for old messages, contacts and any website or application that sends email.
1. Add the domain and prove ownership first
Open Settings → Domains in the Microsoft 365 admin centre and add your domain. Follow the ownership verification step. For a manual DNS setup, copy the TXT verification record Microsoft gives your organisation and publish it at the active DNS host.
In NameUK, open the domain’s DNS records and add that verification value at the root as instructed. Use your own token, not a sample from a guide. Ownership verification is distinct from mail routing: adding the verification TXT does not migrate old messages or create mailboxes.
Sources: Microsoft: connect a domain by adding DNS records ↗ · Microsoft: external DNS records reference ↗
2. Prepare everyone’s mailbox before switching MX
List the addresses that receive mail today, including sales, accounts, staff aliases and shared inboxes. Add the domain to Microsoft 365, then prepare the required users, licences and mailboxes before changing the incoming mail destination. Microsoft explicitly advises preparing mailboxes first.
Agree how existing messages and contacts will move. Changing DNS controls where new messages arrive; the old provider retains existing data unless you migrate it. Keep access to the previous service during the transition and check its cancellation terms before closing it. Do not overlook a rarely used invoices address simply because your main mailbox works.
Sources: Microsoft: connect a domain by adding DNS records ↗ · Microsoft: use a custom email domain ↗
3. Add only the records your organisation needs
Microsoft’s setup wizard lists the required records for your chosen services. Copy the exact MX target, priorities and other values from your own admin centre. Do not invent the tenant-specific destination by converting the domain name yourself. Review the final hostname shown by the NameUK form before saving.
| Record | Purpose | Where the value comes from |
|---|---|---|
| TXT verification | Prove control of the domain. | Your Microsoft domain setup wizard. |
| MX | Route new incoming mail. | Your organisation’s exact Exchange Online target. |
| Autodiscover CNAME | Help supported mail apps find settings. | Microsoft’s current setup instructions. |
| SPF TXT | Identify authorised sending systems. | A combined policy for every legitimate sender. |
| DKIM CNAMEs | Publish Microsoft’s signing-key locations. | The two selector targets supplied for your domain. |
Sources: Microsoft: connect a domain by adding DNS records ↗ · Microsoft: external DNS records reference ↗
4. Preserve the website and review all email senders
You can normally change email routing without changing your website’s root A/AAAA or www records. Leave those website entries in place. Do not clear the DNS zone to make room for Microsoft’s records. Search Console verification and other service TXT entries can remain alongside email configuration.
Keep one SPF policy at a hostname. If your website, booking tool or mailing platform also sends mail for the domain, review those services before editing the existing policy. Adding a second TXT value beginning v=spf1 is not the way to combine senders. Follow the individual providers’ requirements and check the complete policy.
5. Enable signing and test real delivery
After publishing the DKIM entries supplied by Microsoft, complete its DKIM enablement step in the relevant security settings. Publishing a CNAME and enabling a service are separate checks. Review DMARC alongside SPF and DKIM using the documented email setup for your organisation.
Run Microsoft’s domain checks, then send mail to and from an unrelated mailbox. Check a normal user, shared mailbox and alias. Reply to the received message, test Outlook setup and test your website contact form or transactional messages. If something fails, record the sender, recipient, time and bounce explanation before changing more DNS.
Common questions before you commit
Must I transfer the domain to Microsoft? No. You can keep it registered and renewed with NameUK. Does changing MX transfer old email? No. Plan that migration separately. Can I keep two email services? Complex split delivery requires a deliberate mail-routing design; publishing competing MX records is not a general way to distribute staff between providers.
What if mail still reaches the old provider? Check the current authoritative MX answer and allow cached records to expire. Keep the former mailbox service available while you verify the cutover. If some addresses fail, confirm the corresponding recipients exist in Microsoft 365 before changing DNS again.
Compare the Microsoft subscription and domain renewal as separate ongoing costs. NameUK’s current affordable UK domain registration and renewal offer is below. The domain price does not include Microsoft licences, mailbox migration work or a Microsoft 365 subscription.
Provider instructions checked on 15 October 2026. Use the current values shown in your own provider account when making changes.
Further readingMicrosoft: connect a domain by adding DNS records ↗Microsoft: external DNS records reference ↗Microsoft: use a custom email domain ↗Microsoft: configure DKIM for a custom domain ↗Extension rules and provider processes can change. Check the current registrar instructions before a registration, transfer or renewal.
Low-cost registration. Affordable UK renewals.
Register .co.uk for £9.99 for one year, with annual renewal currently £9.99. Or choose a new three-year .co.uk registration for £25.99. Check the selected name and term before payment. Future renewal prices can change.