(42301) 2001 UR163 (provisional designation 2001 UR163) is a resonant trans-Neptunian object located in the outermost region of the Solar System.

The object measures approximately 352 kilometers (220 miles) in diameter with a high albedo and stays in an uncommon orbital resonance (4:9) with Neptune.

It was discovered on 21 October 2001 by astronomers of the Deep Ecliptic Survey program at Kitt Peak National Observatory near Tucson, Arizona, United States.

[9] The body's observation arc begins with a precovery, published by the Digitized Sky Survey and taken at the Siding Spring Observatory in July 1982.

The analyzed data indicate the presence of 20% water ice, 60% amorphous silicates, and 20% organic compounds, including complex ones such as tholins.