List of longest rivers of the United States

For the longest rivers in each U.S. state, see List of longest rivers of the United States by state.

The longest rivers of the United States include 38 that have main stems of at least 500 miles (800 km) long. The main stem is "the primary downstream segment of a river, as contrasted to its tributaries".^[1] The United States Geological Survey (USGS) defines a main-stem segment by listing coordinates for its two end points, called the source and the mouth. Some well-known rivers like the Atchafalaya,^[2] Willamette,^[3] and Susquehanna^[4] are not included in this list because their main stems are shorter than 500 miles.

The Mississippi drainage basin includes the Missouri and the Mississippi rivers, the two longest main-stem rivers in the United States, as well as 18 more of the rivers on this list. The Mississippi main stem is highlighted in dark blue.

Seven rivers in this list cross or form international boundaries. Three—the Milk River, the Red River of the North, and the Saint Lawrence River—begin in the United States and flow into Canada; two do the opposite (Yukon and Columbia). Also a segment of the Saint Lawrence River forms the international border between part of the province of Ontario, Canada, and the U.S. state of New York. Of these seven rivers, only the Milk River crosses the international border twice, leaving and then re-entering the United States.^[5] Two rivers, the Colorado and the Rio Grande, begin in the United States and flow into or form a border with Mexico.^[5] In addition, the drainage basins of the Mississippi and Missouri rivers extend into Canada,^[6][7] and the basin of the Gila River extends into Mexico.^[8]

Sources report hydrological quantities with varied precision. Biologist and author Ruth Patrick, describing a table of high-discharge U.S. rivers, wrote that data on discharge, drainage area, and length varied widely among authors whose works she consulted. "It seems," she said, "that the wisest course is to regard data tables such as the present one as showing the general ranks of rivers, and not to place too much importance on minor (10–20%) differences in figures."^[9]

Table

The primary source for watershed and discharge data in the table below is Rivers of North America. Conflicting data from other sources, if the difference is greater than 10 percent, is reported in the notes. Discharge refers to the flow at the mouth.^{[n 1]} In the "States, provinces, and map" column, the superscripts "s" and "m" indicate "source" and "mouth". Non-U.S. states appear in italics. Except in the "States, provinces, and map" column, abbreviations are as follows: "km" for "kilometer", "mi" for "mile", "s" for "second", "m" for "meter", and "ft" for "foot".

Key
† River is not entirely within the United States.
‡ Watershed is not entirely within the United States.

Longest main-stem rivers of the United States

#	Name	Length	States, provinces, and map[5][11]	Source coordinates[11]	Mouth[5]	Mouth coordinates[11]	Watershed area[12]	Discharge[12]	Photo
1	Missouri River	2,341 mi 3,768 km[13]	Montanas, North Dakota, South Dakota, Nebraska, Iowa, Kansas, Missourim	45°55′39″N 111°30′29″W[14]	Mississippi River	38°48′49″N 90°07′11″W	529,353 mi2 1,371,017 km2[15] ‡[n 2]	69,100 ft3/s 1,956 m3/s [n 3]
2	Mississippi River	2,340mi 3,766 km[17] [n 4]	Minnesotas, Wisconsin, Iowa, Illinois, Missouri, Kentucky, Tennessee, Arkansas, Mississippi, Louisianam	47°14′22″N 95°12′29″W[18]	Gulf of Mexico	29°09′04″N 89°15′12″W	1,260,000 mi2 3,270,000 km2[19] ‡[n 5]	650,000 ft3/s 18,400 m3/s
3	Yukon River	1,979 mi 3,190 km[6] †[n 6]	British Columbias, Yukon Territory, Alaskam	59°35′00″N 133°47′00″W[20]	Bering Sea	62°35′55″N 164°48′00″W[21]	324,000 mi2 839,200 km2[22] ‡[n 7]	224,000 ft3/s 6,340 m3/s
4	Rio Grande	1,759 mi 2,830 km[23] †[n 8]	Colorados, New Mexico, Texasm, Chihuahua, Coahuila, Nuevo León, Tamaulipasm	37°47′52″N 107°32′18″W[25]	Gulf of Mexico	25°57′22″N 97°08′43″W	340,000 mi2 870,000 km2[26] ‡[n 9]	1,300 ft3/s 37 m3/s
5	Colorado River	1,450 mi 2,330 km[16] †[n 10]	Colorados, Utah, Arizona, Nevada, California, Sonoram, Baja Californiam	40°28′20″N 105°49′34″W[29]	Gulf of California	31°48′57″N 114°48′22″W[30]	248,000 mi2 642,000 km2[10] ‡[n 11]	1,400 ft3/s 40 m3/s
6	Arkansas River	1,443 mi 2,322 km [n 12]	Colorados, Kansas, Oklahoma, Arkansasm	39°15′30″N 106°20′38″W[32]	Mississippi River	33°46′30″N 91°04′15″W	160,200 mi2 414,910 km2[33]	35,500 ft3/s 1,004 m3/s
7	Columbia River	1,243 mi[6] 2,000 km †[n 13]	British Columbias, Washingtonm, Oregonm	50°13′00″N 115°51′00″W[34]	Pacific Ocean	46°14′39″N 124°03′29″W[35]	279,548 mi2 724,024 km2[36] ‡[n 14]	273,000 ft3/s 7,730 m3/s
8	Red River	1,125 mi 1,811 km [n 15]	Oklahomas, Texas, Arkansas, Louisianam	34°34′35″N 99°57′54″W[40]	Atchafalaya and Mississippi rivers	31°01′10″N 91°44′52″W	65,590 mi2 169,890 km2[41] [n 16]	30,100 ft3/s 852 m3/s [n 17]
9	Snake River	1,040 mi 1,674 km[16]	Wyomings, Idaho, Oregon, Washingtonm	44°07′49″N 110°13′10″W[42]	Columbia River	46°11′10″N 119°01′43″W	108,000 mi2 281,000 km2[43]	55,300 ft3/s 1,565 m3/s
10	Ohio River	979 mi 1,575 km[44]	Pennsylvanias, Ohio, West Virginia, Indiana, Illinois, Kentuckym	40°26′34″N 80°01′02″W[45]	Mississippi River	36°59′12″N 89°07′50″W	204,000 mi2 529,000 km2[46]	308,400 ft3/s 8,733 m3/s
11	Colorado River of Texas	970 mi 1,560 km[47]	Texass, m	32°40′47″N 101°43′51″W[48]	Gulf of Mexico	28°35′41″N 95°58′59″W	39,900 mi2 103,341 km2[49]	2,600 ft3/s 75 m3/s
12	Tennessee River	935 mi 1,504 km[50]	Tennessees, Alabama, Mississippi, Kentuckym	35°57′33″N 83°51′01″W[51]	Ohio River	37°04′02″N 88°33′53″W	40,880 mi2 105,870 km2[52]	71,000 ft3/s 2,000 m3/s
13	Canadian River	906 mi 1,458 km[16]	Colorados, New Mexico, Texas, Oklahomam	37°01′11″N 105°04′33″W[53]	Arkansas River	35°27′12″N 95°01′58″W	47,130 mi2 122,070 km2[54]	6,100 ft3/s 174 m3/s
14	Brazos River	860 mi 1,390 km[55]	Texass, m	33°16′07″N 100°00′37″W[56]	Gulf of Mexico	28°52′33″N 95°22′42″W	44,620 mi2 115,566 km2[57]	8,800 ft3/s 249 m3/s
15	Green River	760 mi 1,230 km[58]	Wyomings, Colorado, Utahm	43°09′13″N 109°40′18″W[59]	Colorado River	38°11′21″N 109°53′07″W	44,900 mi2 116,200 km2[60]	6,100 ft3/s 172 m3/s
16	Pecos River	730 mi 1,175 km[61]	New Mexicos, Texasm	35°58′34″N 105°33′29″W[62]	Rio Grande	29°41′59″N 101°22′17″W	44,000 mi2 113,960 km2[63]	71 ft3/s 2 m3/s
17	White River (Arkansas)	720 mi 1,159 km[64]	Arkansass, m, Missouri	35°50′20″N 93°36′16″W[65]	Mississippi River	33°57′05″N 91°04′53″W	27,872 mi2 72,189 km2[66]	34,600 ft3/s 979 m3/s
18	James River [n 18]	710 mi 1,140 km[67]	North Dakotas, South Dakotam	47°28′53″N 99°51′32″W[68]	Missouri River	42°52′17″N 97°17′26″W	20,942 mi2 54,240 km2[69]	854 ft3/s 24.2 m3/s[69] [n 19]
19	Kuskokwim River	702 mi 1,130 km[70]	Alaskas, m	63°05′16″N 154°38′33″W[71]	Bering Sea	60°04′59″N 162°20′02″W	48,000 mi2 124,319 km2[72]	67,000 ft3s 1,900 m3/s
20	Cimarron River	698 mi 1,123 km[73]	Oklahomas, m, Colorado, Kansas	36°54′24″N 102°59′12″W[74]	Arkansas River	36°10′14″N 96°16′19″W	19,510 mi2 50,540 km2[75]	1,500 ft3/s 42 m3/s
21	Cumberland River	696 mi 1,120 km[76]	Kentuckys, m, Tennessee	36°50′42″N 83°19′26″W[77]	Ohio River	37°08′36″N 88°24′27″W	17,930 mi2 46,430 km2[78]	30,400 ft3/s 862 m3/s
22	Yellowstone River	678 mi 1,091 km[79]	Wyomings, Montana, North Dakotam	43°59′18″N 109°55′45″W[80]	Missouri River	47°58′42″N 103°58′56″W	70,400 mi2 182,336 km2[81]	12,800 ft3/s 362 m3/s
23	North Platte River	665 mi 1,070 km[82]	Colorados, Wyoming, Nebraskam	40°38′23″N 106°24′19″W[83]	Platte River	41°06′50″N 100°40′33″W	34,885 mi2 90,352 km2[82]	770 ft3/s 21.9 m3/s
24	Milk River	625 mi 1,005 km[6]†[n 20]	Alberta, Montanas, m	48°51′20″N 113°01′10″W[85]	Missouri River	48°03′26″N 106°19′07″W	22,332 mi2 57,839 km2[86] ‡[n 21]	670 ft3/s 18.9 m3/s
25	Ouachita River	605 mi 974 km[87]	Arkansass, Louisianam	31°41′56″N 94°19′57″W[88]	Black River	31°37′53″N 91°48′25″W	24,886 mi2 64,454 km2[89]	29,800 ft3/s 843 m3/s
26	St. Lawrence River	600 mi 965 km[90] †[n 22]	New Yorks, Ontarios, Quebecm	44°05′55″N 76°23′28″W[92]	Gulf of St. Lawrence	49°40′00″N 64°30′00″W[93]	620,000 mi2 1,600,000 km2[94] ‡[n 23]	440,000 ft3/s 12,600 m3/s [n 24]
27	Gila River	600 mi 960 km[95]	New Mexicos, Arizonam	33°10′47″N 108°12′22″W[96]	Colorado River	32°43′11″N 114°33′19″W	57,850 mi2 149,832 km2[97] ‡[n 25]	210 ft3/s 6 m3/s [n 26]
28	Sheyenne River	591 mi 951 km[98]	North Dakotas, m	47°41′46″N 100°29′52″W[99]	Red River of the North	47°01′25″N 96°49′31″W	8,800 mi2 23,000 km2 [n 27]	288 ft3/s 8.2 m3/s [n 28]
29	Tanana River	584 mi 940 km [n 29]	Alaskas, m	63°02′57″N 141°51′52″W[103]	Yukon River	65°09′38″N 151°57′37″W	44,000 mi2 114,000 km2[104]	41,800 ft3/s 1,185 m3/s
30	Smoky Hill River	576 mi 927 km[98]	Colorados, Kansasm	38°57′01″N 102°34′49″W[105]	Kansas River	39°03′36″N 96°48′04″W	19,260 mi2 49,900 km2 [n 30]	1,542 ft3/s 43.7 m3/s [n 31]
31	Niobrara River	568 mi 914 km[98]	Wyomings, Nebraskam	42°49′15″N 104°38′50″W[107]	Missouri River	42°45′58″N 98°02′50″W	12,600 mi2 32,600 km2[108]	1,700 ft3/s 49 m3/s	A small river flows through a field of grass and yellow flowers.
32	Little Missouri River	560 mi 900 km[109]	Wyomings, Montana, South Dakota, North Dakotam	44°32′25″N 104°59′57″W[110]	Missouri River	47°36′38″N 102°52′24″W	8,310 mi2 21,500 km2[111] [n 32]	450 ft3/s 13 m3/s[111] [n 33]
33	Sabine River	553 mi 890 km[112]	Texass, Louisianam	32°48′29″N 95°55′14″W[113]	Gulf of Mexico	29°59′08″N 93°47′26″W	9,756 mi2 25,268 km2[114]	8,400 ft3/s 238 m3/s
34	Red River of the North	550 mi 890 km[115] †[n 34]	North Dakotas, Minnesotas, Manitobam	46°15′52″N 96°35′55″W[117]	Lake Winnipeg	50°23′47″N 96°48′39″W[118]	111,000 mi2 287,500 km2[119] ‡[n 35]	8,300 ft3/s 236 m3/s
35	Des Moines River	525 mi 845 km[120]	Minnesotas, Missouri, Iowam	44°05′02″N 95°41′17″W[121]	Mississippi River	41°22′52″N 91°25′21″W	12,018 mi2 31,127 km2[122]	6,400 ft3/s 182 m3/s
36	White River (Missouri River)	506 mi 815 km[123]	Nebraskas, South Dakotam	42°41′10″N 103°50′14″W[124]	Missouri River	43°42′50″N 99°28′01″W	10,200 mi2 26,418 km2[125]	570 ft3/s 16 m3/s
37	Trinity River	506 mi 815 km[126]	Texass, m	32°47′54″N 96°53′52″W[127]	Galveston Bay	29°44′35″N 94°42′12″W	17,970 mi2 46,540 km2[128]	7,800 ft3/s 222 m3/s
38	Wabash River	503 mi 810 km[98]	Ohios, Indianam, Illinoism	40°21′07″N 84°45′57″W[129]	Ohio River	37°47′53″N 88°01′38″W	32,950 mi2 85,340 km2[130]	1,001 ft3/s 28 m3/s

Map

Map of North America showing all rivers on this list.

See also

• List of rivers of the United States
• List of rivers of the United States by discharge
• List of longest rivers in the United States by state
  • List of longest streams of Idaho
  • List of longest streams of Minnesota
  • List of longest streams of Oregon
• List of rivers by length

Notes

1. Dams, diversions for agriculture, and other human alterations to rivers have greatly affected the discharge of some rivers over time. For example, the virgin discharge of the Colorado River is estimated to have been 20,000 ft³/s (566 m³/s) compared to 1,400 ft³/s (~40 m³/s) in 2005.^[10]
2. Of the total, 10,700 mi² (28,000 km²), about two percent of the basin, is in Canada.^[6][7]
3. Kammerer: 76,200 ft³/s (2,160 m³/s).^[16]
4. Kammerer: 2,340 mi (3,766 km).^[16] The Atlas of Canada: 2,348 mi (3,779 km).^[6]
5. Of the total, 10,700 mi² (27,800 km²), less than one percent of the basin, is in Canada.^[6][7]
6. Of this total, 714 mi (1,149 km) are in Canada. This amounts to about 36 percent of the main-stem length.^[6]
7. The Atlas of Canada also lists the total basin size at 324,000 mi² (839,200 km²), split between 125,000 mi² (323,800 km²), about 39 percent, in Canada and 199,000 mi² (515,400 km²), about 61 percent, in the United States.^[6]
8. Kammerer: 1,900 mi (3,100 km).^[16] University of Texas (UT): 1,799 mi (2,895 km).^[24] The river forms the U.S.–Mexico border for 1.251 mi (2,013 km) (about 70 percent of its main-stem length) from El Paso to the Gulf of Mexico.^[24]
9. Rivers of North America says that of this total only about 170,000 mi² (450,000 km²) of the basin contribute water to the river.^[26] The University of Texas (UT) says, "The river collects rain, snowmelt and spring water from an area [of] about 215,338 mi² [557,722 km²] including closed basins."^[24] It says that 87,020 mi² (225,380 km²) of the basin (about 48 percent), not counting closed basins, are in Mexico, while 93,821 mi² (242,994 km²) (about 52 percent) are in the United States.^[24] Kammerer cites a total basin size of 336,000 mi² (870,000 km²).^[16]
10. According to the Utah Division of Water Resources, 75 mi (121 km) of the river are in Mexico. This amounts to about 5 percent of the main-stem length.^[27] Of this, 17 mi (27 km) form the border between Mexico and the United States.^[28]
11. The United Nations Environment Programme cites a total basin size of 246,000 mi² (637,000 km²), split between 2,000 mi² (5,200 km²) (about 1 percent) in Mexico and 244,000 mi² (632,000 km²) (about 99 percent) in the United States.^[28]
12. Derived by subtracting the length of the East Fork Arkansas River of roughly 16 mi (26 km)^[31] from Kammerer's total of 1,459 mi (2,348 km).^[16]
13. About 498 mi (801 km) are in Canada.^[6] This amounts to about 40 percent of the main-stem length.
14. The Atlas of Canada lists the total watershed at 259,200 mi² (671,300 km²), split between 39,700 mi² (102,800 km²) (about 15 percent) in Canada and 219,500 mi² (568,500 km²) (about 85 percent) in the United States.^[6] Kammerer's figure for the total watershed is 265,000 mi² (690,000 km²).^[16]
15. This is the combined length, 1,360 mi (2,190 km),^[37] of the main stem, Prairie Dog Town Fork Red River, and Tierra Blanca Creek minus the lengths of the latter two, 160 mi (260 km)^[38] and 75 mi (121 km).^[39] Kammerer gives the length as 1,290 mi (2,080 km).^[16]
16. Kammerer: 93,200 mi².^[16]
17. Kammerer: 56,000 ft³/s (1,600 m³)^[16]
18. Also known as the Dakota River or Jim River and not to be confused with the James River of Virginia.
19. This is the average discharge for the years 1982–94, derived by adding the discharge for each of these years and dividing by 13.
20. According to The Canadian Encyclopedia, a 110-mi (170 km) stretch of the river flows through Canada. This amounts to about 18 percent of the main-stem length.^[84]
21. The Atlas of Canada: 23,600 mi² (61,200 km²) split between 8,300 mi² (21,600 km²) (about 35 percent) in Canada and 15,300 mi² (39,600 km²) (about 65 percent) in the United States.^[6]
22. According to the U.S. Army Corps of Engineers, a 115-mi (185 km) stretch of the river forms part of the U.S.–Canada border. This amounts to about 19 percent of the main-stem length.^[91]
23. Kammerer: 396,000 mi² (1,030,000 km²).^[16] The Atlas of Canada: 519,000 mi² (1,344,200 km²), of which 324,000 mi² (839,200 km²) (about 62 percent) is in Canada and 195,000 mi² (505,000 km²) (about 38 percent) is in the United States.^[6]
24. Kammerer: 348,000 ft³/s (9,900 m³/s).^[16]
25. Of this total, 232 mi² (600 km²) (about 0.4 percent) are in the Mexican state of Sonora, and the rest is in the United States.^[8]
26. Rivers of North America describes the discharge as less than 210 ft³/s (6 m³/s.
27. This is the size of the basin upstream of a stream gauge near Kindred and at river mile 67.9 (river kilometer 109.3).^[100]
28. This is the average flow measured by a stream gauge near Kindred and at river mile 67.9 (river kilometer 109.3).^[100]
29. The main-stem length is calculated by subtracting the length of the Nabesna River from Kammerer's total of 659 mi (1,061 km).^[16] The Nabesna River is roughly 75 mi (121 km) long, calculated by adding the 60 mi (97 km) from the Nabesna mouth to Camp Creek^[101] to the distance, 15 mi (24 km), from Camp Creek to Nabesna Glacier,^[102] Kammerer's most remote source for the Tanana.
30. Reflects only that part of the basin above a stream gauge at river mile 43.3 (river kilometer 69.7) near Enterprise.^[106]
31. Measured by a stream gauge at river mile 43.3 (river kilometer 69.7) near Enterprise.^[106]
32. This is only a close approximation of the entire basin. It does not include a small fraction of the basin below the river gauge, located about 25 mi (40 km) upstream of the river mouth.
33. This is the average discharge for the years 1990–2010, derived by adding the discharge for each of these years and dividing by 21.
34. According to the Minnesota Department of Natural Resources, 394 mi (634 km) are in the United States. This amounts to about 72 percent of the main-stem length.^[116]
35. Of the total basin, 53,500 mi² (138,600 km²) (about 48 percent) are in Canada and 57,500 mi² (148,900 km²) (about 52 percent) are in the United States.^[6]