is an English professional footballer who plays as a defender for Isthmian League Premier Division club St Albans City.

Bostwick started his career at Millwall, and played regularly for the club's under-18 team and reserve team. At the age of 17, he joined Conference National club Crawley Town on a work experience loan during the latter stages of 2005–06 season. Bostwick played regularly for Crawley until he was recalled by Millwall in January 2007. He was told he was surplus to requirements at the club and subsequently signed for Rushden & Diamonds on an 18-month contract, where he played eight matches before being released by Rushden at the end of the 2006–07 season. He joined Ebbsfleet United in August 2007 ahead of the 2007–08 season, helping Ebbsfleet win the FA Trophy at Wembley Stadium in May 2008. Bostwick rejected a contract offer from Ebbsfleet, and signed for Stevenage Borough shortly after the FA Trophy success. He played regularly in the club's defence and midfield throughout his time at Stevenage, winning the FA Trophy once again in May 2009 and helping the club earn back-to-back promotions from the Conference Premier into League One.

After making 206 appearances during his four years at Stevenage, Bostwick signed for Championship club Peterborough United in July 2012, where he spent five seasons; playing 228 times and helping the club win the Football League Trophy in 2014. He then joined Lincoln City ahead of the 2017–18 season, winning the EFL Trophy in 2018 before being named the club's Player of the Year as they finished the 2018–19 season as League Two champions. Bostwick signed for fellow League One club Burton Albion in August 2020, before rejoining former club Stevenage, initially on loan in January 2022, and then on a permanent basis in May 2022. After helping Stevenage earn promotion into League One during the 2022–23 season, Bostwick joined Boston United of the National League North in June 2023.