Pennsylvania One Call System is open 24 hours a day, 365 days a year. This includes all state holidays. The following are the state holidays that will not be included in the calculation of the three business days notice.
| Pennsylvania State Holidays | 2021 |
| New Years Day | January 1 |
| Martin Luther King, Jr. Day | January 18 |
| President's Day | February 15 |
| Memorial Day | May 31 |
| Independence Day | Observed July 5 |
| Labor Day | September 6 |
| Columbus Day | October 11 |
| Veteran's Day | November 11 |
| Thanksgiving Day | November 25 |
| Day after Thanksgiving | November 26 |
| Christmas Day | Observed December 24 |
| News Years Day 2022 Observed | Observed December 31 |