After not being selected in the 2003 NFL draft, Hanson was signed by the San Francisco 49ers as an undrafted free agent.

In 2006, shortly after the conclusion of the NFL Europe season, Hanson was signed to a two-year contract by the Philadelphia Eagles.

That season, Hanson played in all sixteen games for Philadelphia, starting one, garnering 26 solo tackles, nine assists, and thirteen pass deflections.

[6] In 2007 season, he again played in all sixteen games, starting four, and made 45 solo tackles and seven assists, along with a sack and a fumble recovery.

On the Thanksgiving night game against the Arizona Cardinals, Hanson started in place of an injured Samuel and recorded his first career interception.

In week 17 against the Dallas Cowboys, he returned a fumble 97 yards for his first career touchdown, as part of a victory that sent the Eagles to the playoffs.