A providing device according to the present application includes a detecting unit and a providing unit. The detecting unit detects a function, from among functions used for communication with an authentication server that authenticates the identity of a user by verifying a signature of authentication result information that is information created by adding the signature using a predetermined key to an authentication result obtained by an authentication device that performs personal authentication on the user and that is information processed by a specific authentication procedure, that is not held by a terminal device that is used by the user. The providing unit provides the function detected by the detecting unit to the terminal device that is used by the user.