His contract with Hayes & Yeading expired on 10th January and, despite an offer that would have made him the highest paid player at the club, he has chosen to leave.
The 20-year-old former Reading keeper joined United in August 2015 after showing well during pre-season.
He had been with the Reading academy since 2003, aged 7, and received a two-year scholarship at 16 before being signed as a professional and advancing into the first-team squad.
During this time had loan spells with Oxford United, Metropolitan Police, Harrow Borough, Farnborough and Nuneaton Town.
Hayes & Yeading will be seeking compensation either in agreement with Basingstoke, or through the tribunal system.