Top 10 Longest Rivers in the United States

1. Missouri River – 2,341 mi (MT, ND, SD, NE, KS, MO, IA). Longest US river; Mississippi tributary.
2. Mississippi River – 2,340 mi (MN, WI, IA, IL, MO, KY, TN, AR, MS, LA). 2nd longest; main stem of largest N. American system.
3. Yukon River – 1,979 mi (AK, Canada). 3rd longest; major salmon run.
4. Rio Grande – 1,900 mi (CO, NM, TX). 4th; border river, vital for irrigation.
5. Arkansas River – 1,460 mi (CO, KS, OK, AR). 5th (by length); Mississippi tributary.
6. Colorado River – 1,450 mi (CO, UT, AZ, NV, CA). 6th; lifeline of Southwest, heavily dammed.
7. Columbia River – 1,243 mi (WA, OR, Canada). 7th; massive hydroelectric.
8. Red River of the South – 1,290 mi (TX, OK, AR, LA). 8th; Mississippi tributary.
9. Snake River – 1,038 mi (ID, WA, OR). 9th; Columbia tributary, Hells Canyon.
10. Ohio River – 981 mi (PA, OH, WV, KY, IN, IL). 10th; largest Mississippi tributary by volume.

Lengths vary by source; Arkansas/Colorado/Red River order sometimes differs. Missouri > Mississippi by ~1 mile.