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Host the user portal on a custom domain

Configure a branded subdomain for your Letterbook user portal.

Last updated June 23, 2026

What this guide covers

Use a custom domain when you want customers to access the Letterbook user portal from your own brand, such as help.company.com or support.company.com.

We recommend hosting the portal on a subdomain of your main domain. For example, if your main website is company.com, use a subdomain like:

  • help.company.com
  • support.company.com
  • docs.company.com
  • portal.company.com

Avoid hosting the portal on your root domain, such as company.com, because that domain is usually reserved for your marketing site or application.

Why use a subdomain

A subdomain keeps the portal clearly connected to your company while separating it from your main website and app infrastructure.

Subdomains are easier to manage because:

  • They avoid conflicts with your primary website.
  • They can point directly to Letterbook without moving your root domain.
  • They are easy for customers to recognize.
  • They let your support portal have its own SSL certificate and routing.

Setup steps

  1. Choose the portal subdomain you want customers to use.
  2. Open the user portal domain settings in Letterbook.
  3. Enter the subdomain, such as help.company.com.
  4. Copy the DNS record Letterbook provides.
  5. Add the DNS record at your DNS provider.
  6. Return to Letterbook and verify the domain.
  7. Wait for SSL provisioning to complete.
  8. Open the subdomain in a browser and submit a test ticket.

DNS record setup

Letterbook will show the DNS record needed for your portal domain. In most cases, custom portal domains use a CNAME record that points your subdomain to a Letterbook-hosted target.

Copy the record exactly as shown:

  • Name: the subdomain or host, such as help
  • Type: usually CNAME
  • Value: the Letterbook target shown in the UI

DNS providers format hostnames differently. Some ask for only help; others accept the full hostname help.company.com. If verification fails, check whether your DNS provider automatically appends the root domain.

SSL and verification

After DNS verifies, Letterbook provisions SSL so customers can load the portal over HTTPS.

SSL provisioning may take a few minutes after the DNS record is correct. Do not send customers to the custom domain until the portal loads successfully over HTTPS.

Recommended launch checklist

  • The custom domain resolves to the Letterbook portal
  • HTTPS works without browser warnings
  • Branding is correct on the portal
  • Search returns expected articles
  • A test ticket creates a conversation in Letterbook
  • Links from your app or website point to the new subdomain

Troubleshooting

The domain is not verifying

Confirm the DNS record name, type, and value match Letterbook exactly. If the record name includes the root domain twice, remove the extra domain from the host field.

The portal loads without HTTPS

Wait for SSL provisioning to finish, then refresh. If the DNS record was recently changed, SSL can lag behind DNS verification.

The wrong site loads

Check for an existing DNS record using the same subdomain. A subdomain can only point to one destination at a time.

Customers still use the old portal URL

Update links in your app, website footer, help menu, onboarding emails, and support auto-replies to use the custom subdomain.