| Year | Won | Margin | Democratic | Republican | Total |
|---|---|---|---|---|---|
| 2024 | R | 22,327 | 73,165 | 97,256 | |
| 2020 | R | 20,530 | 67,294 | 91,160 | |
| 2016 | R | 10,288 | 42,650 | 62,371 | |
| 2012 | R | 8,337 | 44,698 | 54,226 | |
| 2008 | R | 10,826 | 37,311 | 49,529 | |
| 2004 | R | 7,513 | 35,633 | 44,018 | |
| 2000 | R | 5,465 | 25,481 | 32,461 | |
| 1996 | R | 4,816 | 17,637 | 25,020 | |
| 1992 | R | 3,364 | 11,310 | 21,476 | |
| 1988 | R | 3,054 | 13,306 | 16,565 | |
| 1984 | R | 1,846 | 12,049 | 13,977 | |
| 1980 | R | 1,678 | 10,181 | 12,197 | |
| 1976 | R | 1,893 | 5,944 | 8,414 | |
| 1972 | R | 956 | 5,176 | 6,662 | |
| 1968 | R | 975 | 3,226 | 5,000 | |
| 1964 | R | 1,789 | 2,534 | 4,323 | |
| 1960 | R | 1,298 | 2,876 | 4,174 | |
| 1956 | R | 877 | 3,172 | 4,049 | |
| 1952 | R | 1,076 | 2,941 | 4,017 | |
| 1948 | R | 1,580 | 2,029 | 3,617 | |
| 1944 | D | 1,694 | 1,575 | 3,270 | |
| 1940 | D | 1,993 | 1,625 | 3,621 | |
| 1936 | D | 2,005 | 1,145 | 3,164 | |
| 1932 | D | 1,648 | 1,378 | 3,047 | |
| 1928 | R | 857 | 1,686 | 2,547 | |
| 1924 | R | 868 | 1,181 | 2,149 | |
| 1920 | R | 1,008 | 1,138 | 2,156 | |
| 1916 | D | 1,397 | 703 | 2,104 | |
| 1912 | D | 842 | 712 | 1,633 | |
| 1908 | D | 810 | 740 | 1,556 | |
| 1904 | D | 761 | 718 | 1,484 | |
| 1900 | D | 1,003 | 409 | 1,414 | |
| 1896 | D | 1,210 | 170 | 1,380 | |
| 1892 | — | — | — | — | |
| 1888 | — | — | — | — | |
| 1884 | — | — | — | — | |
| 1880 | — | — | — | — | |
| 1876 | — | — | — | — |
Washington County's population has more than doubled since 2000, driven by retirees and families relocating from California and the Mountain West. That growth has done little to shift its deep-red presidential margins, which have held above R+50 for over a decade.
The Republican margin in Washington County reached its widest at seventy-three points in 1984. The margin in 2024 was fifty-two points, in line with the county's deep historical pattern.
Washington County's loyalty is rooted in its place. Median household income of $80,632, a 85% non-Hispanic-white share, and a population of 196,431 together describe a community whose political habits are deeply settled. The county's voting pattern over the last decade is most similar to that of Iron County and Bonneville County.