The present school was refounded as King Alfred's Grammar School in 1850, and was built in a 13thc style by G. Street and J. B. Clacy (1849-50). Incorporated in it was the 12thc. doorway of the former Latin School (once sited in the churchyard of the parish church of St Peter and St Paul, but discontinued in 1832). This doorway became the entrance to a classroom, which was subsequently used as a chapel and later still functioned as Wantage Register Office. This was the case in 1998, but the Registry Office later moved to a new site in the Civic Hall, and has since closed. The doorway is now part of the school again, and is at the N end of a chapel-like block on the N side of Portway, with a bellcote over its S gable.

The original site of the doorway is uncertain. Wantage Grammar School was founded in Wantage churchyard following letters patent of Elizabeth I issue in 1597, and the doorway is known to have been taken from that site to the new Grammar School, built in 1849. The doorway was some 450 years old when Elizabeth's school was built, however, and probably came from a religious building. The likeliest would seem to be the parish church of St Peter and St Paul, but it has not been possible to confirm this and more research is needed.

The beakhead ornament is related to that from Reading Abbey (now in Reading Museum and Art Gallery), arguably the earliest appearance of this type of decoration in England, and the form of the bird beakheads is similar to Reading too.