Two main ferry companies provide service between mainland ports and the islands.
- Miller Boat Line, established in 1905, is the only ferry company transporting vehicles as well as passengers from their Catawba Dock near Port Clinton, OH and South Bass (Put-in-Bay) and Middle Bass Islands. The Miller Ferry makes the trip to South Bass Island across the South Passage in 18 minutes and is located 2 miles from downtown Put-in-Bay. They only accept vehicle reservations to Put-in-Bay from commercial carriers, but reservations are required for all vehicles traveling to Middle Bass Island.
- Put-in-Bay's Jet Express transports passengers only between downtown Port Clinton, OH and downtown Put-in-Bay. The ferry service also offers passenger ferry service between downtown Sandusky, OH and downtown Put-in-Bay. Passengers can also ride between both mainland ports and Kelleys Island, or purchase a combination ticket for both islands from either mainland port.