Shedding
Their coats shed differently: the Chesapeake Bay Retriever moults most as the seasons change, the Curly-Coated Retriever holds loose hair until it is brushed or clipped out.
Grooming
The Curly-Coated Retriever needs more grooming, brushing a few times a week, where the Chesapeake Bay Retriever needs a brush once a week.
Temperament
They differ most on affection (Chesapeake Bay Retriever: affectionate on its own terms; Curly-Coated Retriever: likes its own space) and on loyalty (Chesapeake Bay Retriever: sticks close to its people; Curly-Coated Retriever: bonded to its family).
Alike
They are much the same size as adults, about 31 kg (68 lb) for the Chesapeake Bay Retriever and 33 kg (73 lb) for the Curly-Coated Retriever.