The population was 399 at the 2020 United States Census[3] Before the New Haven vicinity was settled, it was inhabited by multiple indigenous cultures.

Some countryside southeast of the village near the Wabash was formerly the location of a village of a Late Woodland people known as the "Duffy Complex"; the location is now an archaeological site known as the Duffy site.

[4] New Haven is located in the northeast corner of Gallatin County at 37°54′26″N 88°7′37″W / 37.90722°N 88.12694°W / 37.90722; -88.12694 (37.907113, -88.126954).

Illinois Route 141 passes through the northern part of the village, leading east 5 miles (8 km) to the Indiana border at the Wabash River and 13 miles (21 km) to Mount Vernon, Indiana, and west 12 miles (19 km) to U.S. Route 45 northwest of Omaha, Illinois.

Shawneetown, the Gallatin County seat, is 17 miles (27 km) to the south.