The league features internal promotion and relegation with up to three levels in some regions; only clubs in the top tier Premier Division are eligible to compete for the national championship.

Now featuring numerous MLS U19 teams including LAFC, Philadelphia Union and LA Galaxy, the Premier Division is widely regarded as occupying the unofficial 4th tier of US Soccer.

Former member club PSA Elite is known for reaching the fourth round of the 2014 and the 2015 Lamar Hunt U.S. Open Cup by knocking out higher-level professional teams.

[9] The UPSL's participants in the 2016 US Open Cup altogether defeated teams from the PDL (Timbers U-23), NPSL (Sacramento Gold), and USL (Orange County Blues FC).

[10] For the 2025 U.S. Open Cup, Soda City FC earned the automatic first round slot by winning the 2024 UPSL Spring season.