A Practice Note explaining how to compute time periods in Pennsylvania civil litigation, including computing time periods measured in days, weeks, months, and years. This Note also explains how to account for weekends and legal holidays, how to calculate a deadline when the prothonotary's office (or other office designated for filing) is unexpectedly closed on the last day of the deadline, and the circumstances in which deadlines may be extended, including filing extensions for public emergencies, such as the 2019 novel coronavirus disease (COVID-19) outbreak.