What an email host does
Behind a single address there are four jobs, and an email host does all of them:
- Receiving. A server listens for SMTP connections from other mail servers, checks that the recipient exists on a domain it hosts, scores the message for spam and files it into the right mailbox and folder.
- Storing. Messages, attachments and folder state are kept on the host, within a quota per mailbox, and backed up.
- Access. Webmail, a mobile app and IMAP let people read and organise the same mailbox from any device.
- Sending. Outgoing mail is authenticated, signed with the domain's DKIM key and delivered to the recipient's host, with the SPF and DMARC records that make it trustworthy.
How mail reaches a hosted mailbox
When someone sends to you@yourcompany.co.zm, their mail server looks up the MX record for yourcompany.co.zm, connects to the hostname it names, and hands over the message. Nothing about the domain itself has to change when you move between hosts; only that one DNS record does. That is why email hosting is separate from domain registration and from web hosting, even when one company sells all three.
Hosted or self-hosted?
| Hosted email | Self-hosted email | |
|---|---|---|
| Who runs the servers | The provider | Your team |
| Where data lives | Provider's infrastructure (with ontechmail: Zambia) | Your premises or private environment |
| Setup effort | Minutes, plus DNS records | Servers, storage, backups, monitoring |
| Best for | Most businesses, schools, NGOs | Regulated bodies, air-gapped networks |
ontechmail is unusual in offering the same platform both ways. Most customers use the hosted service; those with residency or isolation requirements run it on their own infrastructure. The self-hosted email page covers the trade-offs.
What to check before choosing an email host
- Standard protocols. IMAP and authenticated SMTP submission, so you are never locked into one client.
- Authentication records. The host should give you SPF, DKIM and DMARC records and sign outgoing mail per domain, not from a shared key.
- Encryption in transit. HTTPS for webmail, TLS on IMAP and SMTP ports.
- Account security. Two-factor authentication and recovery codes.
- Data location and exit. Know which country holds the data and confirm you can export everything over IMAP.
- Attachment and storage limits. ontechmail supports attachments up to roughly 50 MB; storage is set per plan.
- Support you can reach. A provider in your time zone who answers the phone.
Email hosting with ontechmail
ontechmail hosts mailboxes on your own domain on Ontech-operated infrastructure in Lusaka, with webmail, the OMail app, IMAP on 993, POP3 on 995, SMTP on 465 and 587, and a REST API. The Starter plan is free for one domain and three mailboxes; larger plans are quoted on request. DNS hosting and websites with automatic HTTPS are available in the same account, so the whole online presence of a domain can be managed in one place. See email hosting in Zambia for the local specifics and business email for the feature list.
Frequently asked questions
What is email hosting?
Email hosting is a service that runs the mail servers for your domain: it receives mail addressed to your domain, stores each mailbox, and sends outgoing messages on your behalf. Your domain's MX record tells the internet which host to deliver to.
What is the difference between email hosting and web hosting?
Web hosting serves your website over HTTP; email hosting receives, stores and sends your mail over SMTP and IMAP. They can be bought together or separately, and a domain's DNS can point each service at a different provider. ontechmail offers both under one account.
Can I keep my existing domain when I change email host?
Yes. You keep the domain at your registrar and only change its DNS records, chiefly the MX record. Mail continues to arrive at the old host until the MX change propagates, so there is no gap if you set up mailboxes first.
How much storage do I get?
Each mailbox has a storage quota set by the plan; attachments up to roughly 50 MB are supported. The free Starter plan covers a small team, and the Business plan adds more mailboxes and storage.