KPMG UK has announced a 13% fall in profits.
The Big Four firm saw its profitability drop to £349m from £403m in what it dubbed a "challenging year".
Its tax division reported the worst performance with a 3% revenue loss at £380m against £392m in 2011, while management consulting was clearly the golden goose with 2012 revenues up 12% from £255m in 2011 to £286m this year.
Risk consulting delivered an 11% uplift at £250m, while transactions and restructuring came in at £389m and audit - "a highly competitive market which is also very cost-conscious" - at £469m, both recorded more modest growth of 3% each.
However, the firm's overall 2012 UK revenues recorded a 4% rise to £1,774m, up from £1,707m in 2011.
A spokesperson for the firm said the drop in profitability was primarily down to "a mixture of staff costs and investment", as "there were job losses over the summer when 275 people were made redundant and we bought IT advisory firm Xantus".
The Xantus deal was announced in October 2011. The business, which boasts a number of FTSE 100 clients, had a £16m recorded income in 2010/11, with offices in Cheshire and London.
KPMG UK's staff numbers were up from 10,150 in 2011 to a 2012 average of 10,574. The number of partners nudged up from 579 to 602.
Simon Collins, KPMG UK senior partner, said: '2012 was a challenging year. We were pleased to grow revenues, and some parts of our business such as risk consulting and management consulting have seen double digit growth. We continue to invest in these areas and in helping our clients prepare for growth.
'Our profitability fell because of investment and because we maintained high staff levels in some areas of our business in anticipation of a wider economic recovery that failed to materialise. Nonetheless we continue to invest for the future. There are signs that market conditions are improving slowly, and the first few months of our new financial year have been encouraging.'
KPMG International saw its revenues rise by 6.4% from 2011 to $23bn (£14.25bn) for the year ending 30 September 2012.