Email Setup Wizard

Proton Mail + IONOS

Set up Proton Mail email on IONOS

The records Proton Mail needs, written with the field names IONOS uses (Host name, Points to, Value, Alias), in the order to add them.

  • 5 steps
  • 8 DNS records
  • Sources checked October 21, 2026

Before you start

  1. Have your Proton Mail account ready. Some values are unique to your account and come from the Proton Mail settings (Domain names).
  2. Open DNS at IONOS: Sign in at login.ionos.com, select Menu, then Domains and SSL. Under Actions for your domain, select the gear icon, then DNS.
  3. Keep both tabs open and add the records below one at a time.

Records to add

Copy each value with the button next to it. Rows marked “Copy from Proton Mail settings (Domain names)” are unique to your account.

Domain verification Proves you own the domain Type TXT Host name Leave empty Value Copy from Proton Mail settings (Domain names) Looks like: protonmail-verification= followed by a code Priority n/a TTL Default
MX records Where incoming email goes Type MX Host name @ Value mail.protonmail.ch Priority 10 TTL Default
MX records Where incoming email goes Type MX Host name @ Value mailsec.protonmail.ch Priority 20 TTL Default
SPF record Which servers may send as you Type TXT Host name Leave empty Value v=spf1 include:_spf.protonmail.ch ~all Priority n/a TTL Default
DKIM A signature on every message Type CNAME Host name protonmail._domainkey Value Copy from Proton Mail settings (Domain names) Priority n/a TTL Default
DKIM A signature on every message Type CNAME Host name protonmail2._domainkey Value Copy from Proton Mail settings (Domain names) Priority n/a TTL Default
DKIM A signature on every message Type CNAME Host name protonmail3._domainkey Value Copy from Proton Mail settings (Domain names) Priority n/a TTL Default
DMARC record What to do with fakes · recommended Type TXT Host name _dmarc Value v=DMARC1; p=quarantine Priority n/a TTL Default

Step by step in IONOS

Verify your domain

Your email provider needs proof that you control this domain before it accepts email for it.

Type
TXT
Host name
Leave this field empty
Value
Copy it from Proton Mail settings (Domain names) (see below)

Where to find your value

In Proton Mail open Settings → Domain names, add your domain and copy the verification value.

It looks like: protonmail-verification= followed by a code

In IONOS

  1. Select Add record, then the TXT section.
  2. Leave Host name empty for your bare domain, paste the Value, and choose a TTL.
  3. Select Save.

Point your MX records

MX records tell every other mail server where to deliver email for your domain. They must point to your provider and nowhere else.

Type
MX
Host name
@
Priority
10
Points to
mail.protonmail.ch
  • Delete any other MX records, or make sure Proton's have the lowest priority number.
Type
MX
Host name
@
Priority
20
Points to
mailsec.protonmail.ch

In IONOS

  1. Select Add record, then the MX section.
  2. Enter @ as Host name, the mail server in Points to, and the Priority. Choose 1 hour for TTL.
  3. Select Save.
  4. If other MX records are listed, delete each one with the Delete record (trash can) icon.
  5. Repeat for each MX record above.

Add the SPF record

SPF is a TXT record that lists the services allowed to send email from your domain, so receivers can spot forgeries.

Type
TXT
Host name
Leave this field empty
Value
v=spf1 include:_spf.protonmail.ch ~all
  • Keep one SPF record. To keep an existing one, add include:_spf.protonmail.ch right after v=spf1.

In IONOS

  1. Select Add record, then the TXT section.
  2. Leave Host name empty for your bare domain, paste the Value, and choose a TTL.
  3. Select Save.

Set up DKIM

DKIM publishes a public key so receivers can confirm your messages really came from you and were not changed on the way.

Type
CNAME
Host name
protonmail._domainkey
Alias
Copy it from Proton Mail settings (Domain names) (see below)

Where to find your value

Copy the exact target from the DKIM tab of your domain in Proton Mail settings.

  • Add all three DKIM records; Proton rotates keys between them.
  • Some hosts reject a trailing period on CNAME values. If yours does, remove the final dot.
Type
CNAME
Host name
protonmail2._domainkey
Alias
Copy it from Proton Mail settings (Domain names) (see below)

Where to find your value

Copy the exact target from the DKIM tab of your domain in Proton Mail settings.

Type
CNAME
Host name
protonmail3._domainkey
Alias
Copy it from Proton Mail settings (Domain names) (see below)

Where to find your value

Copy the exact target from the DKIM tab of your domain in Proton Mail settings.

In IONOS

  1. Select Subdomains, then Add subdomain, and enter the record's name (for example autodiscover).
  2. Under Actions for the new subdomain, select the gear icon, then DNS.
  3. Select Add record, then the CNAME section.
  4. Enter the target in the Alias box, tick the I am aware disclaimer if it appears, and select Save.
  5. Repeat for each CNAME record above.

Add the DMARC record (recommended)

DMARC tells receivers what to do with mail that fails SPF and DKIM, and where to send reports about it.

Type
TXT
Host name
_dmarc
Value
v=DMARC1; p=quarantine
  • Proton recommends a p=quarantine policy for most domains.

In IONOS

  1. Select Add record, then the TXT section.
  2. Leave Host name empty for your bare domain, paste the Value, and choose a TTL.
  3. Select Save.

Check your setup

Once the records are saved, run a live check. We look up your domain in public DNS and tell you what is right, missing or wrong, with the fix in IONOS’s words.

We only read public DNS records. Nothing is stored.

Common mistakes with Proton Mail on IONOS

Adding only one DKIM record

Proton uses three DKIM CNAMEs (protonmail, protonmail2, protonmail3). Add all three, matching the values in your setup wizard exactly.

IONOS: CNAME records go on their own subdomain

IONOS supports only one top-level CNAME record, so each CNAME is created by first adding a subdomain and then giving it an Alias.

IONOS: MX and a top-level Autodiscover CNAME can't coexist

IONOS doesn't allow a domain to have both an MX record and a top-level Autodiscover CNAME. Microsoft's guide uses the subdomain method above for Autodiscover.

Visit Proton Mail Visit IONOS

Rather have someone do it for you?

Tell us your domain and we will add and verify every record for Proton Mail on IONOS, then send you the check results.

Request done-for-you setup

Proton Mail on IONOS: questions

Where do I add Proton Mail DNS records in IONOS?

Sign in at login.ionos.com, select Menu, then Domains and SSL. Under Actions for your domain, select the gear icon, then DNS. Add each record there, one at a time.

What goes in the Host name field at IONOS?

Leave it empty for records on your bare domain, such as MX and SPF. For the others, enter only the part before your domain, for example protonmail._domainkey. IONOS adds your domain automatically.

Do I need to delete my existing MX records at IONOS?

Delete any other MX records, or make sure Proton's have the lowest priority number.

Where do I get my Proton Mail DKIM record?

Copy the exact target from the DKIM tab of your domain in Proton Mail settings.

Sources

Every value and step on this page comes from these official pages. Dashboards change, so if something doesn’t match what you see, tell us.

Proton Mail on other hosts

Other email providers on IONOS