Largest River Connected to the Atlantic Ocean: The Amazon

The Amazon River is the largest river by discharge volume entering the Atlantic Ocean—and the largest in the world by any measure.

Key Metrics

• Average discharge: ~209,000 m³/s (more than next 7 rivers combined).
• Drainage basin: ~7,000,000 km² (40% of South America).
• Length: ~6,400–6,992 km (2nd longest after Nile; debated).
• Mouth: Wide estuary (240 km) → Atlantic at 0°30′N, 49°30′W (Brazil).
• Sediment load: ~1.2 Gt/yr (mostly suspended).

Other Major Atlantic Rivers

The Amazon’s freshwater plume extends 100+ km into the Atlantic, altering salinity, color, and biology far offshore—a river that acts like an ocean.