Ryan Jarvis made his U19 Academy debut on 24th March 2001 as a substitute in the 1-0 defeat against Peterborough. He then captained the Under 15 side that won the Northern Ireland Milk Cup in July 2001. The Canaries youngsters began by beating Coventry City 3-1 with goals from Liam Hunn, Ryan Jarvis and Danny Crow. A New York Select XI was dispatched 4-0 before Everton were defeated 3-2 ( Ryan Jarvis, Lee Howlett and Josh Clarke) in the Quarter Final. Two goals from Lee Catchpole were enough to give the young Norwich side vivotry over the Republic of Ireland Development Squad after the Irish took the lead. The final against Hearts was 0-0 at the end of the 30 minutes each way game, and went into golden goal time, in which Jarvis scored the winning goal. This meant that Norwich became the first side to win the Milk Cup on three occasions adding to their victories in 1991 and 1992. Jarvis was named man-of-the-match for the final and player-of-the-tournament for the 2001 Milk Cup, in the under-15 age group.

Ryan was called up for the England Under 16s on 18th October 2001 for the clash with Spain. Jarvis then underlined his future potential with a sensational first-half performance for England Under-17s against Sweden on 31st July. Defending their Nordic International Tournament title, John McDermott's young charges swept to a 5-2 win over their hosts with 16-year-old Jarvis proving the inspiration as the Fakenham youngster hit four goals before the break. Sammy Morgan stated "He's a lad who's capable of scoring goals, but also capable of scoring different goals." However, Morgan insists that City's latest young prospect has his feet nailed firmly to the floor. The fact that father Neil is the manager of Fakenham Town also helps."His father's a football man and that helps – his parents have been very supportive and the lad himself has got a lovely attitude. Very realistic," said Morgan, well aware of the pressure and pitfalls that can await. "We have a wee chat with him before he goes to tell him what to expect and have another chat when he comes back to discuss how he's got on. What we try and do is just make sure that in amongst all these little successes we all stay realistic and keep his feet on the floor. But he's a good, decent kid." (Thanks to the Pink Un for quotes from Sammy Morgan)

Ryan then followed England's Nordic Up victory with a fine performance for Norwich's academy side in the Doetinchem international tournement where Norwich finished third, beating FC Copenhagen in the play-offs. Jarvis finished second leading scorer in a tournament which also included Ajax, Anderlecht and a USA representative side.

Whilst still a First Year Academy scholar at Carrow Road, he was handed the number 23 first team squad number in November 2002. This came after he had trained with the first team, and had come very close to being named as a substitute for the home clash against Derby County. Ryan's form for the academy side and England youths forced manager Nigel Worthington to state that Ryan is contracted to the club in face of alleged speculation that Premiership sides were interested in the latest Norwich starlet

In March 2003 Ryan helped England's Under-17s qualify for the European Championship in Portugal by scoring in a 2-0 win over the Czech Republic and playing in a 2-0 win over Scotland. In total, he has 22 schoolboy caps and has scored on eight ocassions.

Ryan wrote himself into the Norwich City history books on April 19th 2003 when his appearance as substitute at Walsall meant that he was the youngest ever player to play for the first team, aged just 16 years and 282 days. His full debut came two days later in the 3-0 home defeat to Wolves.

At the end of July 2003, Ryan signed a three year professional contract with the Canaries, with the option of another year's extension.

The 2003/4 season saw fewer opportunities for Jarvis, especially with the signing of Darren Huckerby and Leon McKenzie. He did though score his first senior goal, making him City's ever youngest goalscorer. His season also suffered from injuries meaning that he missed the FA Youth cup clash at Old Trafford against Manchester United. Surprisingly, he was then called up to the England Under-19 squad for a friendly in Germany on March 30th although he would still qualify at Under-18 level. With no games currently planned at that level, the Under-19 coach Dick Bate is obviously looking to see if he can be of help at the UEFA Under-19 qualifying tournament in Slovenia in May

Althouh Ryan scored a wonderful goal in the Premiership for Norwich against Liverpool at Christmas 2004, he was never a first team regular and at the end of March 2005, Nigel Worthington allowed him to join Colchester on loan until the end of the 2005/6 season.

Unable to break into the first team during 2006/7, Peter Grant allowed him to join Leyton Orient on loan for a month starting 15th February 2007. Although he didn't score on his debut, he netted a hat-trick in his second game - away to Millwall on 20th February 2007 which the O'sn 5-2 and then scored twice on 24th February in a 3-1 home win over Tranmere. In mid-March 2007, Peter Grant allowed Ryan's loan at Brisbane Road to be extended to the end of the season, although there is a 24hour recall clause.

Towards the end of August 2007, Ryan was loaned out once again - this time joining Scottish side Kilmarnock for six months. He returned to Norwich in January and played in the FA Cup draw at home to Bury. Glenn Roeder then decided to let him go out on loan again. Although he was linked with Leyton Orient, he joined Notts County on 31st January 2008 until the end of the 2007/8 season. "I think Ryan in particular needs to be playing first team football if he is going to get his career going and whether we can offer that to him or not remains to be seen," said Roeder

Ryan was one of nine players, including his brother Rossi, to be released by Norwich on 6th May 2008. After being linked with a move to Scandinavia, Ryan in fact returned to Leyton Orient signing a two year contract on 25th June 2008.

On 26th November 2010, Jarvis joined Northampton Town on loan until 3rd January 2011 and will be permitted to play in the Cobbler's Secd Round FA Cup tie the following day. Jarvis had scored 13 goals in 95 games for Orient, including 3 in 11 appearances in the 2010/11 season.

Jarvis returned to Orient and finished the season with 18 appearances and 4 goals. He was released in early May 2011 when his contract expired.. He signed for Walsall at the beginning of July 2011

On 1st March 2012, Ryan joined Torquay on loan until the end of the season. He had scored three goals from 11 starts and 14 substitute appearances for Walsall. "He's played not as regularly as he wanted to at Walsall" said Gulls boss Martin Ling."I know him from my days at Leyton Orient, he came when we were in League One struggling at the bottom of the league and had a great impact on us. He scored loads of goals very, very quickly and got us out of a hole that we were in and it set us up for the rest of the season." Ryan's brother Rossi also played on loan for Torquay.

Ryan made his switch to Torquay permanent on 28th May 2012, signing a one year contract.

In May 2013, Ryan signed for York City, teaming once again with Nigel Worthington.

On 13th January 2015, Ryan joined Aldershot on loan until the end of the 2014/15 season. He had played nine gmaes for the Minsterman in the 2014/15 season without scoring.

Jarvis was released by York on 7th May 2015.

Jarvis joined Lowestoft in 2015.

On 3rd June 2017, he signed for Southern League side Kings Lynn Town. Jarvis played as Kings Lynn won promotion to the National League (North) in 2018/19 after finishing second in the Southern League and winning the play-offs against Warrington Town (Northern League) on 11th May 2019.

On 17th June 2020 it was confirmed that Lynn were winners of the National League South, on a points per game basis due to the premature ending of the season because of Covid-19, and would be promoted into the National League.

At the end of May 2021 it was announced that Jarvis would be leaving the club due to his inability to commit to full time football due to his role with Norwich City Community Sports Foundation.. Although he had become involved with coaching at Lynn, he wasn't ready to hang up his boots and joined Lowestoft on 10th June 2021. "I am delighted to get the paperwork done and finally being able to announce this one," said Lowestoft boss Jamie Godbold "When I heard that Jarv was available I was straight on the phone and if there was someone who'd been in touch with him before me then they must have been with him at that moment!"

Lowestoft were relegated from the Southern League Premier Central Division on 22nd April 2022.

On 6th June 2022 Ryan signed for Leiston. Blues joint boss Darren Eadie said of Ryan’s addition to the squad: -"Ryan will bring valuable experience from higher level clubs in his career, and also leadership on the pitch to help our younger players to develop’.