This article details the five most and least expensive contested primary elections in the House of Representatives. In the 2022 election cycle, 39 of 67 Republican primaries and 27 of 56 Democratic primaries are contested.

The stakes were particularly high for the 2020 elections, and not just for the presidency. At the state-level, some of the most closely watched races were Democratic efforts to flip swing state legislatures blue and take control of the upcoming redistricting process.