Abstract: A bag convertible to a tray. The bag incorporates a tray portion made from a first material, with a second, more flaccid material extending the walls of the tray portion. Score lines along the more flaccid material enable a user to tear the walls from the open end of the bag to the tray portion. With the tray portion of the bag on the lap of the user seated on a seat, the walls of the bag, now separated, may be placed over the abdomen and legs of the user, for example, to intercept spillage, with intervening walls placed underneath the legs of the user to anchor the tray portion on the lap of the user.