---
title: "Add a DKIM record at IONOS, plus SPF and DMARC"
date: "2026-11-06"
author: RocketCart
url: "https://getrocketcart.com/docs/sending-domain/ionos/"
type: docs
---

To send RocketCart emails from a domain at IONOS, add three TXT records in the domain’s **DNS** settings. IONOS activates them right away; other servers on the internet see them within about an hour.

## The records RocketCart needs

| Record | Type | Host name | Value |
| --- | --- | --- | --- |
| SPF | TXT | `@` | `v=spf1 include:mailgun.org ~all` |
| DKIM | TXT | `<selector>._domainkey` | `v=DKIM1; k=rsa; p=<your public key>` |
| DMARC | TXT | `_dmarc` | `v=DMARC1; p=none` |

- Copy every value from the **DNS records** panel in RocketCart (**Settings > Email Settings**). Click **Copy value** on each tab. `<selector>` and `<your public key>` are unique to your store. If the app shows the literal word `<selector>` in Host/Name, your selector is your store name as RocketCart saved it on install: lowercase letters and numbers, hyphens between words, for example `my-store` for “My Store”.
- IONOS adds your domain to the host name. Type `@` for the domain itself, and only the prefix for the others.

## How do I add a TXT record at IONOS?

1. Log in to IONOS and open your domains.
2. Next to the domain, click the gear icon under **Actions** and select **DNS**.
3. Click **Add Record**.
4. Under **Type**, choose **TXT**.
5. In **Host name**, enter the host from the table, for example `_dmarc`.
6. In **Value**, paste the value you copied from RocketCart.
7. Leave **TTL** as it is.
8. Click **Save**.
9. Repeat for the other two records.

Warning

Records only work where your domain’s DNS is managed. If your domain’s nameservers point to another company (for example your web host), add the records there instead.

## What if I already have an SPF record?

A domain can only have one SPF record. With two, both fail. If you already have a TXT record that starts with `v=spf1`, edit that one instead of adding a new one. Put `include:mailgun.org` **before** the `~all` or `-all` at the end:

|  | Value |
| --- | --- |
| Your record now | `v=spf1 include:<your current senders> ~all` |
| After your edit | `v=spf1 include:<your current senders> include:mailgun.org ~all` |

Keep every service your record already lists. Only add `include:mailgun.org`.

Mail servers stop reading an SPF record at `~all` or `-all`, so an include placed after it is ignored. If the value RocketCart suggests ends with `include:mailgun.org`, move that part in front of `~all` when you paste it.

If you use IONOS email, IONOS may already have an SPF record on your domain. Edit that record with the gear icon and add `include:mailgun.org`; don’t create a second one.

## What if I already have a DMARC record?

Keep it and skip the DMARC record. A domain should have only one DMARC record on `_dmarc`, and RocketCart accepts any valid one.

## Verify the records in RocketCart

1. In RocketCart, go to **Settings > Email Settings**.
2. In the **DNS records** panel, click **Verify DNS**.
3. When all three tabs show **Verified** (**Status: 3/3 DNS records verified.**), turn on **Enable custom domain**.

IONOS says changes can take up to 1 hour to reach other servers. RocketCart only checks when you click **Verify DNS**, so click it again later if a record still shows **Missing**. The full flow is in [Set up a custom sending domain](/docs/sending-domain/set-up-sending-domain/). If a record won’t verify, see [Sending domain not verifying](/docs/troubleshooting/sending-domain-not-verifying/).