[Home](./index.md) > [@firebase/auth](./auth.md) > [AuthError](./auth.autherror.md) > [tenantid](./auth.autherror.tenantid.md) ## AuthError.tenantid property The tenant ID being used for sign-in/linking. Signature: ```typescript readonly tenantid?: string; ``` ## Remarks If you use [signInWithRedirect()](./auth.signinwithredirect.md) to sign in, you have to set the tenant ID on [Auth](./auth.auth.md) instance again as the tenant ID is not persisted after redirection.