Despite kicking two goals with his first two kicks in AFL football, Bell failed to make an impression on Dockers' coach Gerard Neesham, who regarded him as too slow a runner to be a successful AFL player. Bell was selected for only two games in 1995.
He was delisted at the end of that season, worked hard to improve his leg speed, and was picked up in the 1996 Pre-season draft, by North Melbourne, where he achieved regular selection and acclaim for his courageous, energetic and skilled performances under coach Denis Pagan. Bell was a premiership player with the Kangaroos in 1996 and 1999, and was named an All-Australian on the bench in 1999. He scored four goals and had 31 possessions in the 1999 Grand Final to be one of the Roos best on the day. In 2000 he won the North Melbourne best and fairest award, the Syd Barker Medal.
At the end of 2000, Fremantle sought his return and Bell was traded back to his original club. As it happened, 2001 was a disastrous season for the Dockers, culminating in the dismissal of coach Damian Drum. Bell won the Doig Medal for the Dockers' best and fairest player that year, and was one of the very few shining lights in a season where the Dockers recorded just two victories. These two wins were in part due to outstanding performances from Bell, who gathered thirty-eight possessions and two goals against Hawthorn in round 18, and forty-four disposals and three goals against Adelaide in round 22. The following year he was appointed captain and in 2003 the club made the finals for the first time. Bell was once again an All-Australian, this time as a follower.
He continued his good form into 2004, winning another Doig Medal. However, Fremantle's team performances were not as good, and in both 2004 and 2005 they narrowly missed making the finals. 2006 started poorly, but Bell was a leading player in Freo's record setting 9-game winning streak to finish in the top four for the first time, and also a member of the team that beat Melbourne in the second semi final to record Fremantle's first ever finals game win.
Despite offering to hand over the captaincy to Matthew Pavlich in 2003, he remained captain for five seasons until the end of the 2006.
At Subiaco Oval, enthusiastic supporters ring a bell (a play on his name) whenever Peter Bell gets a possession. He was president of the AFL Players Association from 2003 until the beginning of 2007.