Rhode Island Sound is the open coastal water body at the mouth of Narragansett Bay, where tidal ocean water mixes with the bay's brackish flow. It is exposed to ocean swell and is considered open water, requiring caution for paddlers. Direct access to the Sound is provided by several public boat ramps, including State Pier #5 near Narragansett and a ramp at Sakonnet Harbor in Little Compton. State Pier #5 offers a more sheltered, beginner-friendly launch into calmer bay waters that lead to the Sound, featuring a parking lot and boat ramp. The Sakonnet Harbor ramp provides access to Sakonnet Harbor and the Sakonnet River before opening into the Sound, but parking for non-trailered vehicles can be limited. Another notable route is the Narrow River, which flows for six miles from Carr Pond to an outlet into Rhode Island Sound, though paddlers should be prepared for potential headwinds when crossing its open ponds.

Paddling on Rhode Island Sound itself involves significant exposure and should be reserved for experienced paddlers with proper equipment and planning. The water is open to ocean swells, and wind-driven waves can build quickly, particularly when a strong southwest wind fills in during morning and afternoon hours. Boat traffic is a major consideration, especially near the mouths of the Sakonnet River and Narragansett Bay, where larger vessels are present. The shoreline features a mix of sandy beaches and rocky, ledge-strewn headlands, such as around Sakonnet Point, which is exposed to swells and is unfriendly for landing. Crossing from areas like Middletown to Sakonnet Point involves navigating deep water where a river meets the Sound, a maneuver best attempted in early morning conditions of light wind and minimal surf. Tide changes are noticeable in the bays and rivers feeding the Sound, and paddlers should plan their timing to account for currents. The best seasons for paddling are spring, summer, and fall, with water clarity varying by season and weather. Wildlife includes eelgrass beds, and the area near Sakonnet Harbor contains the largest eel grass bed in Rhode Island.