[Object] To provide a thermal printer that can prevent deformation of an unprinted label and achieve excellent usability by enabling a printed label to stop at a predetermined position for a long period of time, as well as a program for such a thermal printer. [Means to Achieve Object] A thermal printer includes a control unit that performs control to perform: an option operation, whereby upon completion of printing on a label provided on a continuous label body, the printed label is conveyed to a particular position and then conveyance of the continuous label body is stopped; and a retraction operation, whereby when a preset permitted stop time period has elapsed since the stop of conveyance of the continuous label body without performing next printing during the permitted stop time period, an unprinted label retracts to a retraction position where at least a printing region of the unprinted label is not sandwiched between a platen roller and a thermal head. The control unit can change the permitted stop time period for each type and/or each width of a label to be printed.