A method, computer program product, and system for connection annotation is described. A method may comprise receiving a first indication that a first user attended an event and a second indication that a second user attended the event. The method may further comprise determining whether a first user account associated with the first user and a second user account associated with the second user are connected via an electronic service. The method may also comprise facilitating connection of the first user account and the second user account via the electronic service. The method may additionally comprise generating an annotation corresponding to the connection between the first user account and the second user account based upon, at least in part, the first indication that the first user attended the event and the second indication that the second user attended the event.