# Use the Surface Tag with a Custom Domain Use a custom domain when your Surface forms are served from a verified domain such as `forms.example.com`. The Surface Tag will use that domain for form communication, visitor identification, journey tracking, external-form events, and open triggers. If your forms use `forms.withsurface.com`, you do not need to change your Surface Tag. ## Before you begin [#before-you-begin] You need access to: * Your Surface environment settings * Your DNS provider * Your website's global `` code Only use a domain that is verified in Surface and controlled by your organization. ## 1. Add and verify your domain [#1-add-and-verify-your-domain] 1. In Surface, go to **Settings → Domains**. 2. Click **Add domain** and enter the subdomain you want to use. 3. Add the CNAME record and, when shown, the TXT verification record to your DNS provider. 4. Wait for the DNS changes to propagate. 5. Return to **Settings → Domains** and click **Verify**. Continue only after the domain status is **Verified**. ## 2. Connect the domain to your form [#2-connect-the-domain-to-your-form] 1. Open the form in Surface. 2. Go to **Settings → Custom Domain**. 3. Select the verified domain. Use the custom-domain form URL generated by Surface when embedding or sharing the form. ## 3. Update the Surface Tag [#3-update-the-surface-tag] Add `data-custom-domain` to the Surface Tag in your website's ``: ```html ``` Replace `YOUR_SITE_ID` with the Site ID from **Settings → Overview**, and replace `forms.example.com` with the exact verified domain shown in Surface. We recommend entering the hostname without `https://`. An HTTPS origin such as `https://forms.example.com` also works. Do not include `http://`, a path, query string, fragment, or credentials. Invalid values fall back to `https://forms.withsurface.com`. ## 4. Optimize loading [#4-optimize-loading] If you use connection hints, point them at the custom domain instead of `forms.withsurface.com`: ```html ``` Replace `YOUR_CUSTOM_DOMAIN_FORM_URL` with the full form URL generated by Surface. ## 5. Test the installation [#5-test-the-installation] 1. Publish the website changes. 2. Open a page that contains the Surface Tag and a Surface form. 3. Open and submit the form with test data. 4. Confirm that the response appears in Surface. If the form does not load or tracking is missing, confirm that: * The domain status is **Verified** in Surface. * The form is connected to that domain. * `data-custom-domain` exactly matches the verified hostname. * The form URL uses the same custom domain. To return to the default Surface domain, remove `data-custom-domain` from the Surface Tag and use the form URL generated for `forms.withsurface.com`.