Rathbun Lake is maintained by the U.S. Army Corps of Engineers. Its 11,000 acres are popular for water sports and fishing spring through fall, locally the lake is called Iowa's Ocean. An abundance of public-use land around the lake provides additional recreation opportunities.

Access to the lake is easy from five Corps parks, Honey Creek State Park, and two marinas. Top water sports include sail boating, motor boating, water skiing, and fishing. Three areas are designated swimming beaches. Fishing is popular: in spring for crappie, in summer for walleye and bass, and for catfish, late summer through fall.

There are eight campgrounds around the lake. On the northern shore of the lake Honey Creek State Park offers 828 acres of camping and trails. Marinas at both the east and west ends of the lake provide supplies, slip rentals, campgrounds, and a hotel.

Public-use land around the lake is open for off-lake activities. Hunting, for a variety of birds; pheasant, turkey, duck, quail, and geese, and also for deer, is open in designated areas. Snowmobile trails along the lake's north shore provide 35 miles of winter fun. Birdwatching is popular along the one-third mile Oxbow Trail in the Chariton River Valley. South of the lake, a 125-acre abandoned rock quarry provides year round off-road trails for motorcycle and ATVs. Below the dam, the Rathbun Fish Hatchery raises catfish, walleye, and largemouth bass that stock lakes and rivers statewide. It is open for self-guided tours during weekdays.

Rathbun Lake is located 95 miles southeast of Des Moines and 115 miles west of Burlington. It is accessible via State Highways 2,5, and 142. On the lake there are campgrounds and a hotel. In nearby Centerville there are motels, resorts, and bed and breakfasts.