[Home](./index.md) > [@firebase/auth-types](./auth-types.md) > [PhoneAuthProvider](./auth-types.phoneauthprovider.md) > [providerId](./auth-types.phoneauthprovider.providerid.md) ## PhoneAuthProvider.providerId property Always set to [ProviderId.PHONE](./auth-types.providerid.phone.md). Signature: ```typescript readonly providerId: ProviderId; ```