Vehicles, systems, and methods for delivering natural gas and providing mobile fueling services are disclosed. A method of delivering natural gas includes: delivering a source vehicle to a receiving tank for receiving natural gas at a remote refueling location, the source vehicle having a natural gas engine for driving the vehicle and a source tank disposed onboard the source vehicle for storing the natural gas; and transferring natural gas from the source vehicle to the receiving tank using pressure equalization between the source tank and the receiving tank and using a compressor disposed onboard the source vehicle. The onboard compressor is operatively connected to and powered by the source vehicle engine. The source tank is adapted to store a volume greater than or equal to about 200 DGE of natural gas and supplies natural gas to power the source vehicle engine.