> ## Documentation Index
> Fetch the complete documentation index at: https://docs.tenantcore.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Add a Domain

> Add a domain you already own to a connected Microsoft 365 tenant in TenantCore.

# Add a Domain

TenantCore manages domains you already own.

It does not register or create domains.

## Before you begin

You need:

* a connected Microsoft 365 tenant
* an available domain slot in that tenant
* control of the domain's DNS
* an available DNS setup path: Automatic DNS or manual DNS

Each TenantCore tenant supports up to **12 domains**.

## Add the domain

1. Open the connected tenant.
2. Go to **Domains**.
3. Choose **Add domain**.
4. Enter the domain you already own.
5. Submit the domain.

TenantCore creates the domain resource under the selected tenant and begins the Microsoft/domain setup workflow.

## What happens next

After the domain is added, TenantCore can track:

* Microsoft verification
* MX
* SPF
* DMARC
* DKIM
* mailbox readiness
* DNS provisioning state

The next step is normally DNS configuration.

## Choose a DNS path

### Automatic DNS

Use Automatic DNS when:

* your plan includes it
* your DNS provider is supported
* the provider account can be connected to TenantCore

Current direct-provider support includes:

* Porkbun
* Cloudflare
* Namecheap

### Manual DNS

Use manual DNS when:

* the provider is unsupported
* provider API access is unavailable
* the provider account does not meet API requirements
* you prefer to publish the records yourself

## Domain ownership boundary

TenantCore only automates DNS for domains already registered inside your TenantCore account.

The Complete API also uses the TenantCore `domain_id`; it does not accept arbitrary external domain names for DNS automation.