Tenon is on the verge of overtaking PKF to become the UK’s ninth largest accounting firm as it closes in on revenues of £250m by 2012.

Russell McBurnie, FD at Tenon, said the firm would post bigger earnings than its rival in September. PKF’s year end is March 2009.

‘I think we’re actually bigger than [PKF in terms of revenue],’ McBurnie said.

McBurnie stressed that like-for-like comparisons were difficult because of different year ends.

Tenon is expected to make £160m for the year to 30 June, while PKF turned over £143m for last year.

PKF senior partner Ian Mills, said: ‘My focus is on PKF and we are pleased as a firm to have achieved another year of solid, double-digit growth in 2007/08.’