The contract has an average annual value of $825,000 and will begin next season.
Chisholm, a fifth-round pick of the Jets in 2018, ranked tied for second among OHL blue-liners with 56 assists and third with 69 points in 2019-20. The 20-year-old was third on the Peterborough Petes in points behind forwards Nick Robertson and Semyon Der-Arguchintsev.
The Jets have a need for defensemen at the NHL level, but their prospect pool is brimming with talent. Winnipeg's top three prospects - Ville Heinola, Dylan Samberg, and Logan Stanley - all play defense.