Anderson was commissioned to write his choral work Bell Mass for Westminster Abbey’s 450th anniversary celebrations of its Collegiate Charter in 2010 – and was first performed by the Choir of Westminster Abbey in a liturgical performance on 29 June, and again at a concert performance at the Abbey on 2 July by the Westminster Abbey choir conducted by James O’Donnell.

Martin Anderson in Tempo Magazine recently expressed his delight in hearing this new choral work:
'To rub shoulders with Purcell, Blow, Gibbons, white and Sheppard on one side and Walton, Elgar and Parry on the other is an auspicious start for any new piece of music - and in one of the nation's most venerated buildings, to boot.  It says quite a bit for Julian Anderson's Bell Mass, given its first concert performance in a programme of Five Centuries of Music Written for Westminster Abbey on 2 July, that it was not overshadowed by the company it kept…
The quasi-medieval effect of the opening phrases of the Kyrie, met by a Messiaen-like organ passage of calm contemplation and then another choral interjection more explicitly contemporarily British, all suggest that Anderson is deliberately anchoring the piece to several points of musical history.  An organ flourish sets the tone for a dancing Gloria that reaches over the Channel to composers like Litaize and Hakim, not least in the brittle quality of the organ-writing; although the music builds up to a powerful climax, it retains an almost playful quality.  The Sanctus swings between an initial urgency and a more contemplative mood, fiercely exciting organ dances alternation with passionate choral statements, the wall-of-sound effect enhanced at one point by independent parts in the four voices.
The organ falls silent for the a cappella Benedictus, marked 'come un rituale antico', where solo bass, tenor and counter-tenor lines edge forth over choral suspensions, imparting a timeless quality and suggesting a quasi-improvised freedom.  The quartet-tones I had noticed in the score (published by Faber) produced not the destabilising chromatic effect that can bring but dissonantly rude, almost rustic, health.  In the brief, fragmented phrases are dropped into place as pieces of mosaic, the line inching forward as if to point to the delicacy of the Lamb, before the bell-like phrases peel out from the chorus, now in six parts (the composer confessed he had found its indication, 'Carillando', in Tippett).  The texture swells to nine parts - its thickest, kept in reserve till now - to rise to a climax on 'pacem' before dying away to a pianissimo close.
In his Bell Mass Anderson has written a work which will take its place in the British choral tradition not just because of its inherent qualities; it's also eminently practical, its modernisms and choir-and-organ scoring well within the range of most competent church choirs and its duration, 17 minutes, trying nobody's patience.  People should soon be singing this piece up and down this land and many others.'
Tempo (Martin Anderson), October 2010