Vassell will team up with the Robins as they bid to end a four-match winless start to life in Evo-Stik League Southern Premier Division at home to Chesham United today (Sports Ground, 3pm).
Vassell should fit in well at Bideford, where his Pilgrims team-mate and fellow 18-year-old Jed Harper-Penman is already a starter on the wing.
Last season Vassell spent a successful loan spell with Conference South club Truro City, where he played out wide.
The Newquay teenager is a nephew of former Aston Villa, Manchester City and England striker Darius Vassell. Bideford's new recruit progressed to a professional contract at Plymouth through Argyle's Cornish development centres.