About 200 lawyers at City legal practices will earn more than £1 million this year, reflecting the dramatic increase in mergers and acquisition work.

Clifford Chance, the world’s largest law firm, will break the million-pound profits per partner barrier for the first time.

That rise alone will account for scores more lawyers earning seven-figure sums.

However, it will be Slaughter and May, the City’s premier corporate firm, whose 120 partners will be earning the most.

They will average about £1.5 million, but longer-serving partners could earn as much as £2 million.

They are expected to include the corporate partners Nigel Boardman and Steve Cooke and the senior partner Tim Clark.

The astonishing rise in profitability mirrors the dramatic rise in the volume and value in UK and international corporate takeover work.

That frequently results in partners as well as junior lawyers, both at UK and US-owned firms, working seven days a week for weeks at a time to seal deals.

Partners at Linklaters, a rival for Clifford Chance in its international reach, should see average profits per partner increase to about £1.2 million, close to a 20 per cent rise compared with last year.

Turnover is expected to rise 15 per cent to more than £1 billion for the first time.

That will mean earnings of up to £1.5 million for Tony Angel, the managing partner, and David Barnes and David Cheyne, who are corporate partners.

Average earnings for partners at Allen & Overy may exceed £800,000 this year, but at least 20 will earn more than £1 million.

Guy Beringer, senior partner, is understood to be one of the highest paid. He said: “It has been a very good year. There is a strong international M&A market and it clearly plays to the strengths of larger firms.”

The rise in profitability at the UK’s largest law firms will narrow the gap in earning power between the City’s top legal eagles and Wall Street’s finest and trigger hopes of a large-scale transatlantic legal merger over the next few years.

Skadden Arps Slate Meagher & Flom, America’s largest law firm, where partners can regularly earn $3 million ($1.5 million) a year, has expanded in London by hiring young lawyers with the promise of big work and big money.

Scott Simpson, Skadden’s London-based cross-borders merger expert, will be one of the City’s highest earners this year.

A senior insider at Clifford Chance, the first firm a year ago to top the £1 billion mark for revenue, said: “We will touch a million pounds each this year. You will see more million-pound earners than ever before. Weekends and Bank holidays have not existed — you have to be available at all times.”

David Childs, the Clifford Chance managing partner, will be one of the firm’s leading earners.

City law firms’ financial year-ends came to a close last week.

Ashurst increased its revenue 28.5 per cent to £275 million.

Average profits per partner are expected to rise up to 20 per cent to about £850,000, but 30 of its 130 equity partners should exceed the £1 million mark.

Similar profits are expected at Herbert Smith.

Geoffrey Green, Ashurst senior partner, would say only that there would be a “definite increase in profitability” but added: “Here corporate work is a greater proportion of the whole. In the slowdown of 2001 London firms suffered more but that gives a big bounce-back now.”

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