Nicky Summerbee had trials at Manchester United, Leicester City, and Norwich City, before joining Swindon Town; where his father, former England international Mike Summerbee, had connections.

Summerbee played 112 games in seven years for the Robins, scoring six goals before Manchester City paid £1.3million for his services. On 10 May 1994, Summerbee won an England 'B' cap in a match against Northern Ireland 'B' at Hillsborough

In 1997, Summerbee joined Sunderland in a £1million-rated swap deal involving Craig Russell.

Summerbee enjoyed some of the finest moments of his career after Sunderland won promotion to the Premiership in 1999, and become an exceptionally under-valued player. Statistics showed him to be a better crosser of the ball than David Beckham, with a crossing accuracy of 36% to Beckham's 27%. As well as crossing, his shooting abilities outshone those of Beckham's, by 53% to 48%.

During that season, an injured Summerbee enjoyed a well-publicised liaison with TV presenter, Melanie Sykes. However, it came at a cost. Summerbee lost his place in the team following his capital night out with Mel and a 4–1 defeat at Arsenal. Whilst he returned after one match, Nicky was substituted in both of his next two games and was relegated to the bench for the next four. He returned triumphantly to the starting eleven by scoring his first goal of the season against Everton. Sadly, it turned out to be his last as a Sunderland player. After this goal, Summerbee was in and out of the side. He finished the season on a high note though, starting in – and starring in – the final three games.

Summerbee was left in the wilderness by boss Peter Reid the following season. He sat on the sidelines for six months until he was given a game for the reserves against Newcastle United. Summerbee was clearly unfit and unhappy, he lashed out at Newcastle United defender Andy Griffin and was immediately substituted before he could be sent off.

Free transfers and quick stays at the likes of Bolton Wanderers (where he scored once against Crystal Palace), Leicester City and Nottingham Forest were followed by a two and a half year stay at Bradford City, which included loan spells at Swindon Town and Tranmere Rovers.

Summerbee latterly played for Nationwide Conference side Tamworth, but was released at the end of the 2005–06 season.