Webmail vs. Quathos Mailer
Two products from the same company that both move email, and are easy to mistake for each other. Quathos Webmail is where your people read and write; Quathos Mailer is where your software sends. Which one you need, and why many companies end up with both.
The difference in one line
A mailbox is opened by a person. A sending API is called by software. Everything else follows from that, including the fact that they are two products, contracted and billed separately.
| Quathos Webmail | Quathos Mailer | |
|---|---|---|
| What it is | A mail server: mailboxes on your domain | A sending API for your application |
| Who uses it | People on your team | Your software |
| How you reach it | A password, in a mail app or the webmail | An API token, over HTTPS |
| Has an inbox | Yes. It receives and stores mail | No. It only sends |
| Typical message | A reply to a customer, written by hand | A receipt, a login code, a password reset |
| Address | you@yourcompany.com | no-reply@yourcompany.com |
| Billed as | Per mailbox, per month, here | By sending volume, in Quathos Mailer |
Which one you need
Answer one question: is there a human on your side of the message?
- Someone in your company needs to read and answer mail at your domain: that is Quathos Webmail, this product.
- Your product needs to send a confirmation, a code or an alert with nobody typing: that is Quathos Mailer.
- A form on your site emails your team, and the team replies: that is both. Mailer delivers it, and the mailbox here is where the reply lands.
The third case is the common one, and it is the reason a `no-reply@` address is a dead end. People answer messages that tell them not to, to add a detail or attach a document. Without a mailbox, that answer goes nowhere.
Using both on the same domain
They are separate products, but they share the domain and the reputation you build on it, so the DNS has to satisfy both at once. Each panel asks for its own records: here, the MX and the mail server’s SPF and DKIM; in Quathos Mailer, the records for delegated sending. Authenticating the domain in one does not authenticate it in the other.
- One SPF record, never two: multiple SPF records make every one of them invalid. Merge the includes into a single record.
- DKIM keys are separate and do not collide: mailbox mail is signed with one selector, Mailer sending with another.
- A single DMARC policy governs both, which is the point of publishing one.
What the mail server is not for
Mailboxes are for correspondence. Bulk or automated sending belongs to a sending product, and not as a formality: the two have different rate limits, different reputation handling and different tooling for bounces and complaints.
- Do not send campaigns or newsletters from a mailbox.
- Do not wire a mailbox into your application as an SMTP gateway. That is what Quathos Mailer is for.
- Do not use one mailbox as a shared account for a whole team; create one per person, so a departure revokes one password.