He was more successful in 1920, when he finished fourth of sixteen candidates and was elected to a two-year term.

He cut short his third term in order to run for mayor in the 1925 election, but finished second in a six candidate race as incumbent Kenny Blatchford took more than fifty-five percent of the vote.

He was re-elected in the 1930 election, when he finished third of nine candidates, but left municipal politics for good at the conclusion of this term.

Collisson ran for the Legislative Assembly of Alberta as a Liberal candidate in the 1930 provincial election.

After leaving politics, Collisson served as the president of Edmonton's community chest from 1941 until 1948.