This chapter estimates current and future sequestration of carbon on lands within U.S. National Park Service units (hereafter NPS units) in the continental USA. We demonstrate a methodology that can be applied to other protected areas in the USA as well. Specifically, using land cover data and associated carbon sequestration rates during a five-year baseline period, this chapter calculates the current tonnage and economic value of vegetative carbon sequestration services on all NPS units located in the continental USA. Average projected sequestration amounts for the period 2006–2050 are also provided based on modeled data. Using conservative assumptions, we find that current average annual carbon sequestration on NPS units’ land amounts to 17.5 million metric tons of CO2, valued at $752.5 million dollars using the Federal interagency working group social cost of carbon damage price of $43/metric ton (updated to 2018 dollars). In the future years through 2050, absent any changes in land management (such as invasive species removal or fire management) carbon sequestration is predicted to fall by 31% to an average of 12.0 million metric tons of CO2 sequestered annually, due to factors such as a warming climate and increased fire hazards.