Free business email in Thailand: set up name@yourbusiness.co.th

Thai businesses run on LINE. Customers book, ask and pay through it, and for a shop or a cafe that may be all that is needed. The moment a business deals with hotels, overseas buyers, condominium owners abroad, or any Thai company with a purchasing department, email returns, and the address on the quotation is what gets judged. A mailbox on your own domain costs a yearly domain fee in baht and nothing more. Here is how the .co.th paperwork works, when .com is the better choice, and the setup from DNS to phone.

Quick answer

Register yourbusiness.co.th through THNIC with your DBD company certificate, or yourbusiness.com at any registrar if you want no paperwork. Create a free OquMail workspace with no card, add the domain, paste four DNS records, click Verify and create your mailboxes. Add the mailbox to the Gmail app or Outlook on your phone over IMAP.

Choosing your domain: .co.th, .in.th or .com

• .co.th: the recognised business ending. THNIC requires proof of a registered Thai company (the DBD certificate) or a trademark, and the name must relate to the company name. Priced in baht.
• .in.th: open to individuals with an ID card, no company needed; fine for a freelancer or a sole trader.
• .com: no documents, registered anywhere in minutes, widely used by Thai businesses for exactly that reason; local buyers trust it.
• Hotels and tour operators often hold both: .com for bookings from abroad and .co.th on Thai paperwork.

Why a domain address matters in Thailand

Export manufacturers in Samut Prakan and Chonburi, hotel groups, condo management companies and the purchasing departments of Thai corporates all treat a free webmail address as a reason to verify a supplier before paying. Foreign guests comparing villas in Phuket or Koh Samui click the listing whose contact address matches the website. Marketplace sellers on Shopee and Lazada need a stable address for seller support, invoices and e-Tax documents. And a business that lives only in LINE has no searchable record of what was agreed with whom, which becomes a problem the first time a customer disputes a price.

Step by step: from domain to working inbox

1. Register the domain: yourbusiness.co.th through THNIC (thnic.co.th) with the DBD certificate, or yourbusiness.com at any registrar. Pay by card, PromptPay or bank transfer.
2. Go to oqumail.com and create a free workspace with your name and a password. No card, no trial countdown.
3. In the dashboard choose Add domain and type the domain. OquMail shows the four DNS records to add.
4. Log in to the registrar, open DNS management, and add the MX, SPF, DKIM and DMARC records exactly as shown.
5. Return to OquMail and click Verify. The live check names any record still missing.
6. Create your mailboxes: info@, sales@, booking@ or accounts@ and one per person. The free plan allows up to 15 mailboxes with 5 GB each.
7. Send a test from webmail to a Gmail address, then add the account to the Gmail app or Outlook on your phone with the settings below.

The four DNS records OquMail needs

• MX — host @, value mail.oqumail.com, priority 10
• SPF (TXT at @) — v=spf1 MX (Mail Exchanger — where incoming email is delivered) a:mail.oqumail.com ~all
• DKIM (TXT at your selector ._domainkey) — v=DKIM1; k=rsa; p=… (the exact key is shown in your OquMail dashboard)
• DMARC (TXT at _dmarc) — v=DMARC1; p=none; rua=mailto:dmarc@yourdomain.com

OquMail connection settings

• Incoming (IMAP): mail.oqumail.com, port 993, SSL/TLS
• Outgoing (SMTP): mail.oqumail.com, port 587, STARTTLS
• Username: your full email address (you@yourdomain.com)
• Password: the same password you use for OquMail webmail

What it costs in Thailand

• The domain: a yearly fee in baht for .co.th or .in.th, or the usual .com price at any registrar
• Mailboxes: free on OquMail, up to 15 with 5 GB each, 250 sends a day per mailbox
• No monthly fee, no hosting plan required

Mistakes common in Thailand

• Letting the web agency register the domain under its own account. Ask for the registrant to be your company and keep the login.
• Putting Thai script in the mailbox name. Keep the address plain ASCII (somchai@, not a Thai form) and put the Thai name in the display name, which renders fine.
• Keeping customer agreements only in LINE. Send the confirmation by email as well, from the company address, so there is a record.
• Mobile networks (AIS, True, dtac) and most home connections block outgoing port 25. Mail apps must use port 587.

Common questions

Can I use a .com if my company is Thai?

Yes. Many Thai companies do, and nothing in the DBD or Revenue Department rules requires a .co.th. The .co.th simply signals a registered company at a glance.

Does it work with Outlook and my phone?

Yes. Add an IMAP account with the settings above in Outlook, Apple Mail or the Gmail app, using your full address as the username.

What are the limits?

15 mailboxes, 3 domains, 5 GB per mailbox, no expiry. Extra mailboxes are added on request without touching DNS.

Want to see how your own domain is set up? Use the free SPF checker, DMARC checker and MX lookup: they run in your browser and store nothing.