How to Authenticate Your Domain Name on IONOS

If your domain’s DNS is managed at IONOS (1&1 IONOS), you authenticate it for systeme.io email by adding three CNAME records and one TXT (DMARC) record under DNS → Add a record. Official help article 3965 walks through copying values from your systeme.io account into IONOS.

This guide covers email sending authentication, not connecting a sales funnel (see article 3962 under Custom Domain).

• Active systeme.io account.
• Domain hosted or registered at IONOS.
• IONOS account login.
• Domain entered in systeme.io without www.
• An active site on the domain when required—see general domain authentication.

1. Log in to systeme.io.
2. Settings → Emails.
3. Start domain authentication.
4. Enter your domain without www → Save.
5. Status shows Pending until DNS propagates.
6. Refresh → click the eye icon to view 3 CNAME + 1 TXT.

Example pattern (your values are unique):

• si942517 → inbound.systeme.io
• systemeio1._domainkey → key1.systeme.io
• systemeio2._domainkey → key2.systeme.io

1. Log in to IONOS.
2. Select the domain to authenticate.
3. Open DNS (DNS settings / DNS zone).
4. Click Add a record for each entry from systeme.io.

Repeat for each CNAME (article 3965):

1. Type: CNAME.
2. Hostname: copy from systeme.io—prefix only (e.g. si942517; if systeme.io shows si942517.yourdomain.com, enter only si942517 when IONOS appends the domain).
3. Points to (Value / Target): paste the target from systeme.io and, per IONOS practice in systeme.io guides, append a period (.) at the end (e.g. inbound.systeme.io., key1.systeme.io., key2.systeme.io.).
4. Click Save.

Expected examples:

• Hostname: si942517 — Points to: inbound.systeme.io.
• Hostname: systemeio1._domainkey — Points to: key1.systeme.io.
• Hostname: systemeio2._domainkey — Points to: key2.systeme.io.

1. Add a record → Type: TXT.
2. Hostname: _dmarc.
3. Value (Points to): e.g. v=DMARC1; p=none; rua=mailto:you@yourdomain.com—replace the placeholder with your real email.
4. Save.
5. Optional: verify with a DMARC checker (e.g. MXToolbox) after propagation.

Keep one _dmarc TXT only.

How to Add a DMARC Record on IONOS (article 3964)

1. Wait for DNS propagation (minutes to 48 hours).
2. Settings → Emails on systeme.io.
3. Confirm Pending → Verified.
4. Verify your sender email address on the same domain.

• Website elsewhere: If IONOS warns that new CNAMEs may conflict with Squarespace or another site, use a subdomain for funnels or consult IONOS before changing root records—email auth records are usually additive but plan carefully.
• IONOS Mail: Keep existing MX records; email-auth CNAMEs work alongside IONOS email when configured correctly.
• Separate record sets: Funnel CloudFront CNAMEs (3962) ≠ email inbound/DKIM CNAMEs (3965)—add both without deleting the wrong set.
• Hostname vs full name: IONOS funnel docs use “part before your domain” for the second CNAME—the same rule applies to DKIM hosts.

Trailing dot on IONOS?

Yes for CNAME Points to values in systeme.io + IONOS guides.

Hostname field?

Prefix only (si942517, systemeio1._domainkey).

Where in IONOS?

Domain → DNS → Add a record.

Funnel vs email?

Different settings and CNAME targets in systeme.io.

DMARC?

TXT, Hostname _dmarc, customized rua email.

• How to Authenticate Your Domain Name for Email Sending
• How to Connect Your IONOS Domain to systeme.io
• How to Add a DMARC Record on IONOS
• How to Improve Your Email Deliverability

Copy records from systeme.io into IONOS DNS, then send with a verified domain.