The altar in St Wilfrid's Chapel is in the Flemish Baroque style and dates from the first half of the eighteenth century.  It was originally the High Altar in the monastic church of St Remy at Rochefort in Belgium.  It came to the oratory from St Servatius' church in Maastricht (Netherlands), having been taken there in 1811 following the suppression of St Remy. The whole chapel was given by Mrs Bowden as a memorial to Father Faber, first Provost of the London Oratory. The body of Father Faber who died in 1863 was burried in the floor before the altar of this chapel in 1952. Father Faber had chosen St Wilfrid as his patron.

St Wilfrid's chapel also contains the altar of the English Martyrs.  Above the altar is the only known religious painting by Rex Whistler.  In the form of a triptych, it shows SS Thomas More and John Fisher on either side with an execution scene at Tyburn in the centre. SS Thomas More and John fisher were canonised in 1935 and the Fathers commissioned this painting in 1938 to commemorate the event.