Email on your own domain - a practical guide
What professional email on your own domain really is, what it costs, and how to set it up yourself step by step - the domain, free mailbox hosting, the DNS records that get your mail delivered, and using the same mailbox from your own software.
Email on your own domain, explained
An address like you@yourcompany.com looks more trustworthy than a free webmail address, keeps your brand in every message, and stays yours even if you change provider later. Most people assume that kind of email is complicated or expensive - a hosting plan, a per-mailbox monthly bill, maybe a whole website to hang it on.
It isn't. Professional email is really just two things: a domain and a place where the mailboxes live. You don't need a website, and for ordinary business correspondence you don't need to pay a monthly fee for the mailboxes either.
This article is a practical walk-through of the whole thing: what it costs, how to set it up yourself step by step - including the DNS records that make mail actually arrive - and how the same mailbox can also be used by your own software. It's written so anyone can follow it; if you'd rather not, there's a way to have it done for you at the end.
Professional email = a domain (a small yearly cost) + a mailbox host (which can be free) + a handful of DNS records so your mail is trusted and delivered. No website required.
What it actually costs
The two parts are independent, and only one of them necessarily costs money. Keeping them separate in your head is the key to not overpaying.
A small yearly cost
You register a domain and renew it once a year. This is the one unavoidable cost - and it is modest, typically in the order of a couple of hundred crowns a year depending on the registrar and the extension.
Can be free
Where the inboxes are hosted is a separate decision. With the right provider, hosting mailboxes on your domain costs nothing - so the domain renewal can be your entire email bill.
Email is delivered through the domain's DNS records - the MX records point incoming mail to your mailbox provider. That works with no website behind the domain at all. A domain can do email only, web only, both, or neither; they're configured separately.
Where the mailboxes live
Every mailbox is ultimately data sitting on a mail server - a machine that speaks IMAP and SMTP, accepts your incoming mail and hands it to your client. So “where the mailboxes live” really comes down to one question: whose server is that - one you run, or one a provider runs for you?
If you already run your own infrastructure, adding a mail server to it is technically no problem - the software is there for the taking. The cost isn't the software, it's the work: a mail server facing the internet has to be kept patched, its sending IP reputation managed, blocklists watched, anti-spam and TLS maintained. On a classic single server that's “just” ongoing labour. In a more advanced cloud or container architecture there's often no persistent box to put it on, so you end up paying for a separate server to host mail as well - now it's labour and money.
The other option is to let a provider run that server for you - the managed route, like Google Workspace, Microsoft 365, Zoho or a paid mailbox at a web host. There's nothing to run and no deliverability to babysit; you pay a monthly fee per mailbox instead. For most teams that's the comfortable default: predictable, hands-off, and someone else owns the headache.
Email Profi by Seznam.cz is the exception: the same managed, hands-off hosting as the paid providers - but free on your own domain, however many mailboxes you create. Beyond the price, what makes it usable in practice:
Free on your domain
Connect a domain you already own, or buy one through Seznam, and run mail on it with no monthly cost - independent of the number of mailboxes.
Manage your own users
Create and manage as many addresses as you need - one mailbox per person, plus role addresses like info@ or sales@.
Generous storage
Mailboxes come with a large storage allowance, so you're not pushed into housekeeping or paid upgrades just to keep receiving mail.
Webmail, calendar, antispam
A familiar web interface with calendar and continuous spam filtering, on any device - nothing to install to get started.
Robotic access, no extra cost
Your own apps can send and read mail over the same IMAP/SMTP - automated, with no separate robot or API fee on top of the free mailbox.
Generous limits
The sending allowances are generous enough for transactional and automated mail, so everyday app traffic doesn't run into walls.
From here on, this guide is written around Email Profi as the concrete example - but the same steps and principles (DNS, IMAP, SMTP) are replicable with any other provider.
Step 1 - Connect the domain
Adding your domain to Email Profi takes one of two forms, and which one you're in decides how much DNS work you do in the next step.
A. Domain at Seznam
If you buy the domain through Seznam (or transfer it there), the DNS is managed for you. The MX records and DKIM signing are set up automatically - you effectively skip Step 2. Simplest possible path.
B. Domain at another registrar
If the domain stays at your current registrar, you keep control of its DNS - and you add a few records yourself so mail is routed to Seznam and trusted by other servers. That's Step 2.
In both cases you add the domain inside the Email Profi administration, where Seznam verifies that you control it. For an external domain (path B), the panel then shows you the exact records to set - and emails them to you as well.
The MX values are generated per domain, so the authoritative source is always your Email Profi panel after you add the domain. Use the values it gives you - the section below explains what each record is for so you know exactly what you're entering.
Step 2 - The DNS records that make mail work
This step only applies to path B (domain at an external registrar). You'll add four kinds of record in your domain's DNS: one to route mail, and three to prove the mail is genuinely yours so it lands in the inbox instead of spam. You add them once.
You enter DNS records wherever your domain's DNS is managed - in practice, the admin panel of the company where you bought (or hold) the domain. Log in there and find the section usually labelled DNS, DNS records, DNS zone or domain settings; you add each record as a row with its type (MX, TXT, CNAME), name and value. No website or hosting is needed - only access to the domain's DNS.
MX - route incoming mail
The MX records tell the internet which servers accept mail for your domain. After you add the domain, Email Profi shows the exact MX hostnames and priorities for it; enter those in your DNS exactly as shown.
Each MX value must end with a trailing dot (.) if your DNS editor expects fully-qualified names, and there must be no old MX records left pointing somewhere else. After saving, a lookup tool such as MxToolbox confirms the records are live (DNS changes can take a while to propagate).
SPF - say who may send for you
SPF is a single TXT record on the domain root that lists who is allowed to send mail as your domain. For Email Profi it is:
| Type | Name | Value |
|---|---|---|
| TXT | @ | v=spf1 include:spf.seznam.cz ~all |
Keep only one SPF record on the domain. If you also send through another service, merge the includes into a single SPF record rather than creating a second one.
DKIM - sign your outgoing mail
DKIM cryptographically signs your messages so receivers can verify they really came from your domain and weren't altered. On an external registrar you delegate signing to Seznam with three CNAME records:
| Type | Name | Value |
|---|---|---|
| CNAME | szn1._domainkey | szn1._domainkey.seznam.cz. |
| CNAME | szn2._domainkey | szn2._domainkey.seznam.cz. |
| CNAME | szn3._domainkey | szn3._domainkey.seznam.cz. |
On a domain whose DNS is at Seznam (path A), DKIM is handled automatically and you don't add these.
DMARC - set the policy
DMARC ties SPF and DKIM together and tells receivers what to do with mail that fails the checks. It's a TXT record named _dmarc. Start in monitoring mode so nothing of yours gets blocked while you confirm everything passes:
| Type | Name | Value |
|---|---|---|
| TXT | _dmarc | v=DMARC1; p=none; rua=mailto:dmarc@yourdomain.tld |
Tightening DMARC later (p=quarantine / p=reject)
p=none only monitors - receivers still deliver mail that fails, and the rua address collects aggregate reports so you can see who sends as your domain. Once the reports show your legitimate mail passing SPF and DKIM, raise the policy to p=quarantine (failures go to spam) or p=reject (failures are refused) to actually stop spoofing. A fuller example: v=DMARC1; p=quarantine; adkim=r; aspf=r; rua=mailto:dmarc@yourdomain.tld; pct=100. Note that Seznam doesn't support forensic (ruf) reports, so leave that tag out.
MX gets mail flowing; SPF, DKIM and DMARC are what keep it out of the spam folder and stop anyone forging your domain. They're a one-time setup, and getting them right is the single biggest factor in deliverability. Skipping them is the most common reason custom-domain mail lands in spam or on a blocklist.
Step 3 - Create mailboxes and connect a client
With the domain connected and DNS in place, the rest is the ordinary email you already know.
Create the mailboxes
In the Email Profi administration you create an address for each person (jan@yourcompany.com) and any shared role addresses you want (info@, sales@). Each mailbox gets its own password. There's no per-mailbox charge, so create as many as the organisation needs.
Use it: webmail or your own app
Webmail in the browser
Read and send straight from the provider's web interface on any computer or phone, with no setup beyond logging in.
Your own mail app
Connect Outlook, Thunderbird, Apple Mail or a phone's mail app over IMAP (receiving) and SMTP (sending) - the standard protocols every mail program speaks.
IMAP keeps the mailbox in sync across every device - read something on your laptop and it shows as read on your phone - while SMTP sends outgoing mail. Because these are open standards you're never locked into one app, and if you ever switch providers you point the domain's DNS somewhere new and your address comes with you. The address belongs to your domain, not to the provider.
Connecting a mail client - what you'll need
Mail clients ask for the incoming (IMAP) and outgoing (SMTP) server names and ports, plus your full email address and mailbox password. IMAP normally uses port 993 and SMTP port 465, both over SSL/TLS. Use the exact server names your provider lists; for Seznam, some setups require enabling external client access or using an app password for the mailbox - covered in the provider's help.
Email your software can use, not just people
Because the mailbox speaks IMAP and SMTP, it isn't only for humans - your own applications can use the same account. Send order confirmations, notifications and reports automatically, or read incoming mail to pull out attachments and trigger a process. A free, standards-based mailbox quietly becomes part of your systems.
To make that wiring straightforward, we maintain an open-source package that talks to any IMAP/SMTP mailbox - Email Profi included - from Node.js / TypeScript:
Vrealmatic/imap-smtp-mailerOpen source · IMAP + SMTP for Node.js / TypeScript · MITView on GitHub →It sends over SMTP and reads over IMAP, with helpers for the fiddly parts: downloading and renaming attachments, filtering messages by sender, date or read status, and ready-made connection presets for common providers (Seznam included) so you don't look up hosts and ports. A small CLI can bulk-download attachments from a mailbox.
Wiring a mailbox into a single script is easy - a few lines to send a message or fetch attachments. Building mail into a product or a business process (queues, retries, templates, validation, logging, audit) is a different job, and one we don't try to cover with a copy-paste guide. If that's where you're headed, see our tools and integrations.
What it's for, and where its limits are
A free, standards-based mailbox fits an enormous range of needs - but it's worth being honest about its edges so you choose it for the right reasons.
Great fit
- everyday business correspondence on your own domain,
- one mailbox per person plus role addresses,
- transactional and operational mail from your apps - confirmations, notifications, reports,
- reading incoming mail to drive a process or grab files.
Not what it's for
- mass commercial campaigns - the free Email Profi terms exclude sending bulk commercial messages,
- large newsletter blasts, which belong on a dedicated bulk-mail service with its own rules,
- anything that ignores per-provider sending limits and ends up looking like spam.
Providers apply technical limits to protect deliverability - for example Seznam caps high-volume senders per IP over a short window (on the order of a hundred thousand messages and a gigabyte of data per five minutes, roughly a hundred messages per SMTP connection) and expects large sends to be spread over time. Normal correspondence and transactional mail never come near these; they matter only at campaign scale - which is a different tool for a different job.
For that scale, use a service built for it. These sit alongside your mailbox - everyday mail stays on Email Profi, only the bulk traffic goes through the dedicated service - and, unlike the mailbox, they're generally always paid:
Marketing & newsletters
Campaign tools with templates, lists and unsubscribe handling.
Mailchimp · Brevo · Ecomail · SmartEmailing
Transactional & API at volume
High-throughput sending from your apps, tuned for deliverability.
Amazon SES · SendGrid · Mailgun · Postmark
Don't want to set it up yourself?
Everything above is deliberately complete - follow it and you'll have working email on your own domain, nothing held back. But it does touch DNS records and mail authentication, which is quick when you've done it before and fiddly when you haven't. If you simply don't want to deal with it, we'll do the straightforward deployment for you for a one-time fee - domain and DNS, the provider configured, your mailboxes created, SPF/DKIM/DMARC done right, and your mail apps connected.
And it doesn't stop at the basic mailbox. If you need more - a campaign or bulk-mail service (Mailchimp, Brevo, Ecomail, SES and the like) set up and connected, or mail wired into your own software and processes - we can set that up and integrate it too. Whatever your needs are, we'll simply solve your mail for you.
You pay once for the setup, and afterwards the only running cost on the basic mailbox is the domain renewal - the hosting itself stays free. Bigger pieces, like a campaign service or a full integration into your systems, are scoped to what you actually need. Either way, start from the contact below.
Summary
The whole setup, at a glance:
- Register a domain - the only unavoidable cost, a small yearly fee. No website needed.
- Choose a mailbox host. Email Profi by Seznam hosts mailboxes on your domain for free, however many you create.
- Connect the domain. On an external registrar, add the DNS records -
MXto route mail, and SPF, DKIM and DMARC so it's trusted and lands in the inbox. - Create the mailboxes and open them in webmail or any IMAP/SMTP client.
- Automate if you want: let your own software use the same mailbox over IMAP/SMTP - e.g. with our imap-smtp-mailer package; deeper integrations live under our tools.
- Campaigns and bulk go elsewhere - a dedicated, paid service, kept off the free mailbox.
Email on your own domain isn't a monthly subscription you have to accept, nor a black box. Done efficiently it's a one-time setup over a free mailbox host - for people and for your software alike.
Don't want to set it up yourself?
We'll handle the deployment for a one-time fee - no monthly cost.