Norwich snapped up third choice Portsmouth goalkeeper Jamie Ashdown on a month-long loan deal on 20th October 2006, making him Peter Grant's first signing as manager. He would compete with Paul Gallacher and Lee Camp for the number one spot at Carrow Road

The Reading-born 25-year-old rose through the ranks with his hometown club the Royals but struggled to displace Marcus Hahnemann and instead gained experience during various loan spells at Gravesend, Bournemouth and Rushden & Diamonds.

In June 2004 the 6ft 3ins former England schoolboy signed a four-year contract at Fratton Park. He spent much of 2005-06 season as Pompey's first choice goalkeeper but his chances were limited with the arrival of Dean Kiely and then David James during the summer of 2006.

Grant said: "He is an excellent keeper. This is about increasing the competitive edge and getting the keepers fighting for that jersey. We have got three quality and experienced keepers. Jamie was a young 'keeper at Reading when I was there and I was impressed with his quality then. We also had him on loan at Bournemouth, but he only played a couple of games then got injured. I've been following his career closely and he is an excellent goalkeeper. He's now got some Premiership experience under his belt with Portsmouth as well, which is important."

Jamie made his Canaries debut the following day in the 1-0 home win over league leaders Cardiff City. In his second appearance, he was sent off as the Canaries crashed 5-0 at Stoke City on 28th October 2006

Jamie returned to Portsmouth after a month apparently unwilling to extend his stay at Carrow Road.

Jamie was primarily understudy to David James but following Pompey's relegation to the Championship at the end of the 2009/10 season, one wonders if James will stay and if Ashdown will get more matchtime. Instead he was released by Pompey in May 2010 but reports suggest that they might re-sign him especially if David James leaves.

James did indeed leave, to join Bristol City and Ashdown was re-signed by Pompey on 9th August 2010. He was their first choice keeper for the 2010/11 season and was in goal when Norwich won 1-0 on 2nd May 2011 to win promotion to the Premier League.

Ashdown and Portsmouth were relegated to League One on 21st April 2012, partly due to the club's perilous finances which had seen them placed in administration and 10 points deducted. Ashdown left the club at the end of the season

After a trial with Middlesbrough, Ashdown signed a one year contract with Leeds on 24th July 2012

Ashdown was released by Leeds in May 2014. He had made just 8 appearances for Leeds, all coming in cup competitions.

In July 2014 Ashdown trialled with both Doncaster Rovers, joining them on their pre-season tour of Portugal, and Blackburn Rovers.

On 29th August 2014, Ashdown signed a short term contract with Crawley until the end of December 2014. "Jamie is very experienced and is a great guy to have around a club," said Reds boss John Gregory. "He is a very positive person who is still as motivated now as he was when he started out in the game."

Jamie left Crawley in November after making 12 appearances, and on 3rd February 2015 signed with Oxford United until the end of the 2014/15 season.

In 2013, Ashdown set up an online business, Trusted Pro Supplements, supplying and offering information to athletes about nutritional supplements that do not feature on banned substance lists and are believed not to be harmful. In 2016 he opened a cafe which went out of business during the Covid-19 lockdown.

He came out of retirement in July 2022 to play for Ascot United for whom he had been goalkeeping coach. He was first choice for the first half of the 2022/23 season but returned to coaching duties and was on the bench as goalkeeping coach when Ascot won the FA Vase beat Newport Pagnell Town 1-0 in May 2023. This was added to their Combined Counties League title and League Cup win.