Firehouse Subs Name of Day promo is back! Get a Buy One Get One FREE Medium Sub deal when your name is chosen as the name of the day. The name for January 15th is Derek. Spelling variations accepted at Franchisee discretion. If that's you, simply show your photo ID at any participating U.S. Firehouse Subs today and get a bogo free medium sub. The names change every day so check back tomorrow if today is not your name's day.