Katahdins are docile so are easily handled. They exhibit moderate flocking instinct. Live weight of a mature ewe in good condition usually ranges from 120 to 160 pounds; a mature ram will weigh 180 to 250 pounds. Average birth weight of twins is about 8 pounds.

Ewes and rams exhibit early puberty and generally have a long productive life. Mature ewes usually have twins, occasionally producing triplets or quadruplets. A well-managed and selected flock should produce a 200% lamb crop. Rams are aggressive breeders, generally fertile year round, and can settle a large number of ewes in the first cycle of exposure. With selection a flock can consistently lamb throughout the year. The Katahdin ewe shows a strong, protective mothering instinct, usually lambs without assistance, and has ample milk for her lambs.

Lambs produce a high quality, well-muscled carcass that is naturally lean and consistently offers a very mild flavor. Lambs are comparable to other medium-sized maternal breeds in growth and cutability. Lambs are desirable for specialty markets at a variety of ages and weights, wethers are appropriate for conventional North American markets at 95 to 115 pounds.

The hair coat of the Katahdin varies in length and texture among individuals and can be any color or color combination. It generally consists of coarse outer hair fibers and an undercoat of fine wooly fibers that becomes very thick and longer if cold weather sets in and day length decreases. This undercoat and some hair naturally sheds as temperature and day length increase seasonally, leaving a shorter, smooth summer coat.