The O'Day 28 is an American sailboat, that was designed by C. Raymond Hunt Associates and first built in 1978.

[1][2][3] The design was built by O'Day Corp. (owned by Bangor Punta and later Lear Siegler) in the United States between 1978 and 1986, but it is now out of production.

[1] [3][4][5] The O'Day 28 is a small recreational keelboat, built predominantly of fiberglass, with wood trim.

It has a masthead sloop rig, a raked stem, a slightly reverse transom, an internally-mounted spade-type rudder controlled by a wheel and a fixed fin keel or centerboard.

Starting with serial number 323, produced in 1980, the boats displace 7,450 lb (3,379 kg) and have a slightly shorter waterline length.