[4] Henry County is part of the Atlanta-Sandy Springs-Roswell, GA metropolitan statistical area.

The Henry County Courthouse is listed on the National Register of Historic Places.

[22] Additionally, a pair of warehouses used to exist along US 23 south of McDonough, one of which was owned by Whirlpool Corporation, and the other by Toys 'R' Us.

Southern Crescent Technical College's Henry County Center (in McDonough) offers programs in Allied Health, Business Technology, Logistics and Supply Chain Management, Computer Information Systems, Personal Services, Public Safety, and Drafting Technology.

In 1920, it was one of three counties in the state (alongside Bleckley and Columbia) to give 100% of the vote to Democratic nominee James M.

[27] The first Republican to win Henry County was Richard Nixon in 1972, doing so with 77.93% of the vote,[28] though it returned to the Democratic column when native Georgian Jimmy Carter won it in 1976 and 1980.

From 1984 to 2004, Henry County was a Republican stronghold, consistent with several Atlanta suburbs, as well as other suburban areas across the country.

In the 2010s, the county rapidly flipped from being safely Republican at the start of the decade to safely Democratic by the end, thanks to explosive population growth that brought an influx of Democratic-leaning minority voters into the county, and a growing Democratic trend among suburban voters in general.

[34] In 2016, Hillary Clinton won the county for the Democrats for the first time in 36 years, by a 4.4 percentage point margin of victory, in spite of the rightward shift taken by the rest of the country.

In 2022, it was one of the few counties where Stacey Abrams improved on her 2018 margin against Republican Brian Kemp even as she performed worse statewide.

[37] A continued improvement on both Clinton and Biden's margin, and the best showing for a non-Georgian Democrat in the county since John F. Kennedy in 1960.