10 Longest Rivers in South America: Complete List With Lengths (2026)

The longest rivers in South America are the Amazon (6,400 km), Parana (4,880 km), Madeira (3,250 km), Purus (3,211 km), Sao Francisco (2,914 km), Tocantins (2,699 km), Araguaia (2,627 km), Paraguay (2,621 km), Orinoco (2,140 km), and Uruguay (1,838 km). Together, they drain the wettest continent on Earth, carrying 28% of the world's freshwater.

Introduction

South America is the wettest continent, and its rivers reflect that abundance. The Amazon alone carries 20% of all river water flowing into the world's oceans -- more than the next seven largest rivers combined.

The continent's rivers drain the Andes, the Amazon rainforest, and the vast grasslands of the south. South America contains 28% of the world's freshwater, more than any other continent. Here are the 10 longest rivers ranked by length.

South America's Longest Rivers: Quick Comparison

1. Amazon River

• Length: 6,400 km (3,976 mi)
• Countries: Peru, Colombia, Brazil
• Discharge: 209,000 m³/s

The Amazon is the undisputed king of South American rivers. It carries more water than the next seven largest rivers combined and drains 40% of the continent. By volume, it is the largest river on Earth, discharging enough water to fill Lake Erie in approximately three hours.

The river has over 1,100 tributaries, 17 of which are longer than 1,500 km. The Amazon basin covers 7 million km², an area nearly as large as Australia, supporting the world's largest tropical rainforest and an estimated 10% of all species on Earth.

2. Paraná River

• Length: 4,880 km (3,032 mi)
• Countries: Brazil, Paraguay, Argentina
• Mouth: Rio de la Plata

The Paraná is the second longest river in South America. It combines with the Uruguay River to form the Rio de la Plata estuary.

The Itaipu Dam on the Paraná generates about 75% of Paraguay's electricity and 17% of Brazil's.

3. Madeira River

• Length: 3,250 km (2,020 mi)
• Countries: Bolivia, Brazil
• Tributary of: Amazon

The Madeira is the Amazon's largest tributary by volume and one of its longest. Its name means "wood" in Portuguese, referring to the massive tree trunks it carries.

The river drains parts of both Brazil and Bolivia.

4. Purús River

• Length: 3,211 km (1,995 mi)
• Countries: Peru, Brazil
• Tributary of: Amazon

The Purús is one of the most winding rivers in the world. Its actual straight-line distance is only about a third of its total length due to extreme meandering.

The river flows through pristine rainforest, much of which remains largely unexplored.

5. São Francisco River

• Length: 2,914 km (1,811 mi)
• Country: Brazil
• Mouth: Atlantic Ocean

The São Francisco is the longest river entirely within Brazil that flows into the Atlantic. It is known as the "River of National Integration" because it connects several Brazilian regions.

Hydroelectric dams on the river provide power to much of northeastern Brazil.

6. Tocantins River

• Length: 2,699 km (1,677 mi)
• Country: Brazil
• Mouth: Amazon estuary area

The Tocantins is sometimes considered a tributary of the Amazon, but technically it empties independently into the Atlantic near the Amazon's mouth.

The Tucuruí Dam on the Tocantins was the world's largest hydroelectric dam in a tropical rainforest when built.

7. Orinoco River

• Length: 2,140 km (1,330 mi)
• Countries: Venezuela, Colombia
• Discharge: 30,000 m³/s

The Orinoco is the third largest river in the world by discharge. Its basin covers about 880,000 km², mostly in Venezuela.

Angel Falls, the world's tallest waterfall, feeds into the Orinoco system via the Caroni River.

8. Paraguay River

• Length: 2,621 km (1,629 mi)
• Countries: Brazil, Paraguay, Argentina
• Tributary of: Paraná

The Paraguay River bisects the country that shares its name. It separates the fertile eastern region from the semiarid Chaco to the west.

The river flows through the Pantanal, the world's largest tropical wetland.

9. Uruguay River

• Length: 1,838 km (1,142 mi)
• Countries: Brazil, Argentina, Uruguay
• Mouth: Rio de la Plata

The Uruguay River forms the western border of Uruguay and gives the country its name. Together with the Paraná, it creates the massive Rio de la Plata estuary.

The river supports significant hydroelectric generation shared between Argentina and Uruguay.

10. Araguaia River

• Length: 2,627 km (1,632 mi)
• Country: Brazil
• Tributary of: Tocantins

The Araguaia flows through central Brazil and contains the world's largest river island, Bananal Island. The island is about 350 km long and 55 km wide.

The river is popular for beach tourism during the dry season when sandy beaches emerge along its banks.

Key Facts

• South America contains 28% of the world's freshwater resources, more than any other continent.
• The Amazon basin covers 7 million km², an area nearly as large as Australia.
• Five of South America's ten longest rivers are tributaries of the Amazon.
• The Pantanal wetland along the Paraguay River floods to an area the size of England during the wet season.
• South America has the highest river discharge of any continent.

Fun Facts

• The Amazon River is home to the pink river dolphin (boto), one of only a few freshwater dolphin species in the world.
• The Casiquiare canal naturally connects the Orinoco and Amazon basins, meaning you can travel by boat between them without leaving the water.
• Bananal Island in the Araguaia is larger than the country of Israel.
• The Pororoca tidal bore on the Amazon can create waves up to 4 meters high that travel upstream for hundreds of kilometers.

Final Thoughts

South America's rivers are superlative in every way. The Amazon leads the pack, but the continent's many other great rivers collectively form one of the most impressive hydrological systems on the planet. From the Amazon's staggering discharge to the Orinoco's unique connection to the Amazon basin via the Casiquiare canal, these waterways demonstrate the extraordinary scale of South American geography.