Richardson began his career with Leeds United where he spent nine years making 186 appearances only interrupted by two loan spells at Stoke City in 2003.

Richardson made his Leeds debut as a second-half substitute against Hapoel Tel Aviv during the 2002–03 UEFA Cup campaign.

He made his full debut against Arsenal at right full-back, a position he was tipped to have on a permanent basis after the retirement of first team regular Gary Kelly.

However, his spell was short lived after Manager Kevin Blackwell chose to play the likes of Danny Pugh and Matthew Kilgallon in that position.

Prior to the 2005–06 campaign, Richardson was subject to two bids from Sunderland, both which were rejected by Leeds' chairman, Ken Bates.

Under new manager Dennis Wise, Richardson played more regularly in the Leeds starting line-up, replacing the injured Gary Kelly at right back.

After a poor performance in this position against Cheltenham Town, Richardson was booed off the pitch by Leeds fans and did not play for a few weeks after.

Leeds United confirmed on 16 June 2009 that they would not continue contract negotiations with him due to the signing of former Northampton captain Jason Crowe.

[10] The new signing was flown back to England immediately for treatment, and the club estimate that he will be out of action for approximately three months, ruling him out of the beginning of the season.