Pilkington was born in New York City to Irish American parents.

After the death of his widowed mother in 1919, his older brother Charlie Pilkington moved the entire family to Meriden, Connecticut.

Shortly after Jackie began boxing in the professional leagues, his older brother took him to Australia, where he fought five bouts in 1927.

In 1930, Pilkington boxed for the Connecticut state title against Bobby Mays in a match set up by the famous manager, Al Weill.

[2][3] In 1931, Pilkington fought his brother's forming sparring partner, featherweight champion Kid Kaplan in Hartford for the New England Lightweight Championship, losing the match to Kaplan in a 10 round match.