Cash-rich, time-poor: it's a phrase that aptly sums up a career in law. Young lawyers can expect to work gruelling hours - 12 hour days, weekend shifts and a Blackberry under the pillow - but are amply rewarded for their efforts, with some City law firms offering starter salaries for newly qualified lawyers of almost £100,000.

Those who stick with it will enjoy salaries that rival those of their high-earning City clients. About 200 lawyers at City law firms will earn more than £1m this year, with some partners earning double that.

The rewards reflect the volume of highly lucrative international merger and acquisition deals handled by London's leading law firms - firms that are known in the profession as the magic circle: Allen & Overy, Clifford Chance, Freshfields Bruckhaus Deringer, Linklaters and Slaughter and May. Partners in these firms - who have a stake in the business and get paid a share of the profits - can earn telephone-number salaries, with the very best taking home £1.5m a year.

Even pre-qualification, there are major rewards for would-be solicitors. The golden ticket is a training contract with one of the big City firms: this means sponsorship while studying for the LPC qualification, followed by a paid two-year apprenticeship. Training contracts are highly competitive and highly prized. Freshfields, for example, pays its trainees' law school fees (about £10,000) and provides a maintenance grant (£6,000) before starting them on a salary of £38,000, which rises to £43,000 halfway through the training contract. On qualification, that salary jumps to £65,000. US law firms in London pay even more.

As trainees gain experience, the pay rises. Annual rises can take the pay of a young solicitor in a big City firm to £90,000 within three years - and that doesn't count a bonus that can be as much as 40 per cent of the basic salary. And there are other perks: health insurance, pensions, gym membership, subsidised staff restaurants and interest-free loans. Clifford Chance employees can also enjoy access to hairdressers, masseurs, dry-cleaners and medical professionals without leaving their plush London offices. "It's about making life easier and more comfortable for our people," says Lynn Johansen, the partner responsible for graduate recruitment at Clifford Chance.

But you don't have to work for one of the magic circle firms to earn big money. In UK commercial firms, newly qualified lawyers can expect to earn upwards of £62,000. For those working outside London, salaries will still be in the £30,000 to £40,000 range, which compares favourably with the take home pay of most 24-year-olds.

It's worth bearing this in mind when weighing up the costs of law school. Solicitor Claire Pearce, 31, qualified four years ago and says it's worth making the investment. "The money worries I had when I was training are far behind me now," says Claire, who specialises in civil litigation at Liverpool-based firm Goldsmith Williams. "Once qualified you can quickly pay off your loans."

Barristers are also well remunerated but the headline earnings of a handful of top silks masks a profession where many juniors struggle to find their feet financially. Around 20 barristers in London are thought to be earning £2m or more a year. Those pupils (trainee barristers) who join the top chambers and specialise in tax, commercial law or chancery can see their earnings overtake their solicitor colleagues in a few years. Barristers are self-employed and get to keep the fees they earn, but this means they must also manage their own tax and make a contribution towards chambers' expenses. Life in the early years can be tough, with some newly qualified criminal juniors lucky to earn £25,000 a year and struggling to juggle tax demands, loan repayments and late payments from clients.

It isn't all about money, however. Whether you decide to become a solicitor or a barrister, the real reward of a legal career is not financial. "We find people are motivated by the intellectual challenge of the job," says Deborah Dalgleish, head of UK trainees at Freshfields Bruckhaus Deringer. "You cannot give legal advice in a vacuum so you are always learning about different industries - even our most senior partners say they are still learning."

The numbers game


Years it takes for a magic circle lawyer to earn around £90,000 a year.


Possible annual bonus in pounds three years after qualification.


Salary in pounds for a newly qualified lawyer at US law firm Latham & Watkins.


The profit in pounds per equity partner at the UK's most profitable firm, Slaughter and May.


The annual earnings in pounds of a handful of top silks.


The revenue in pounds of the law firm Clifford Chance last year.