The Missouri Supreme Court has unanimously blocked the state’s newly enacted congressional map from taking effect in the November 2026 general election, holding that a referendum petition challenging the measure was both valid and timely. The practical result is significant: unless Missouri voters approve the new map, the state will continue using the prior post-2020 census congressional boundaries.

The dispute centered on whether opponents of the map had properly invoked Missouri’s referendum process to suspend the law before it could be implemented.