What you need before you start
Just one thing: a domain registered in your name. It is the part after the @, like yourcompany.com. Without it there is no email on your own domain — the domain is what makes the address yours.
Hosting the mailbox can be free. The domain is not: it is a yearly fee paid to the registrar. A .com.br costs around R$ 40 per year at Registro.br, and a .com runs between R$ 60 and R$ 90. If you already have a website, you probably already have a domain, and can jump to step 2.
A free Gmail account only works with @gmail.com. To use your own domain you need Google Workspace, charged per user every month. The same applies to personal Outlook and Microsoft 365.
Step by step
Register the domain
If you do not have one yet, register at Registro.br (for .com.br) or with an international registrar such as Cloudflare or Namecheap. Pick something short and easy to say over the phone — you will repeat this address a lot.
Add the domain to your provider
Create an account with the service that will host the mailboxes and enter your domain. The provider generates DNS values specific to you — they differ between providers, so always copy the ones shown in your own panel.
Point the MX record
O MX is what tells the world which server receives mail for your domain. Without it, nothing arrives. You add this record in the DNS panel wherever your domain lives — the registrar, or Cloudflare if you use it.
Set up SPF, DKIM and DMARC
These three tell other servers that mail leaving your domain is legitimate. Skipping this step is the number one reason email ends up in spam. They are not optional.
Create the mailbox and send your first message
Once DNS is live, create the address and open it in the browser webmail, or set it up over IMAP in the app you already use. It is worth sending a test message to a Gmail address and checking it lands in the inbox rather than in spam.
What each DNS record does
This is the part that usually looks scary, but it is only four lines of text copied into a panel. Here is what each one means:
| Record | What it does | If it is missing |
|---|---|---|
MX |
Points to the server that receives mail for the domain. | You receive nothing. |
SPF |
Lists who is allowed to send on behalf of your domain. | Your messages land in spam or get rejected. |
DKIM |
Digitally signs every message, proving it was not tampered with. | Reputation drops and delivery suffers, especially at Gmail. |
DMARC |
Says what to do when SPF or DKIM fail, and sends you reports. | Your domain is left open to spoofing by third parties. |
How it works at Core9 Email
No free plan you create a mailbox on your own domain, with no credit card and no expiry date. The panel shows the four records ready to copy and checks by itself whether each one is live, querying your domain's own servers directly.
- Webmail in the browser, plus IMAP, POP3 and SMTP for the app you prefer.
- DKIM configured automatically — you never generate a key.
- Spam filtering active from day one.
- If you need more mailboxes later, plans start at R$ 19.90/month.