New Horizons was planned as a voyage to the only unexplored planet in the Solar System. When it was launched, Pluto was still classified as a planet. It was reclassified as a dwarf planet by the International Astronomical Union (IAU) in 2006.

Distance-encounter operations at Pluto, with the onboard LORRI imager plus Ralph telescope, will begin January 4, 2015. Pluto and Charon will be only a few pixels across. On May 5, 2015, resolution will exceed the Hubble's resolution.

New Horizons is intended to fly within 10,000 km (6,200 mi) of Pluto with a relative velocity of 13.78 km/s (49,600 km/h; 30,800 mph) at closest approach, and will come as close as 27,000 km (17,000 mi) to Charon.

After passing by Pluto, New Horizons will continue farther into the Kuiper belt for encounter with one more additional Kuiper belt objects of the order of 50–100 km (31–62 mi) in diameter.