Compared to investment banking, salaries in accounting are low. While front office investment bankers in their 30s are earning over £200k ($310k) on average, front office accountants of a similar age can expect to achieve £114k if they're male and just £72.4k if they're female, according to a salary survey supported by the ICAEW - the UK's leading accounting exam body. That same salary survey suggests that accountants with 20 years' post-qualification experience earn an average of 'just' £113k - big in comparison to the UK average, a pittance in comparison to the sums that equally seasoned investment bankers have come to expect.

Does this mean the Big Four (Deloitte, EY, PwC and KPMG) are best avoided if you aspire to maximize your income? Not necessarily. Recruiters and Big Four insiders point out that some areas of public practice pay better than others.

"Anything advisory in the Big Four will pay more," says Glenn Roberts, an associate director at recruitment firm Marks Sattin. "Areas like M&A, tax advisory, transaction services, restructuring and forensics will typically pay a lot more than audit."

Another recruiter, who poaches people from the Big Four to work in the banking sector, says senior managers (who tend to have between five and eight years' post-qualification experience) can expect to earn salaries of £75k in audit, but £95k to £100k in the highest paid advisory area of M&A and corporate finance. "The corporate finance guys can get bonuses of up to 30%," confirms Roberts. "In audit the bonuses are around 10%."

Given that it takes around four years to become qualified in accounting, the implication is that auditors earn total packages of £82.5k nine years after leaving university. In investment banking, similar pay packages are on offer just two years in.

A recent study by Emolument.com, the real time salary benchmarking company, confirms the general rule that audit jobs pay less than other Big Four roles. As accounting firms build up their consulting divisions, consultancy is instead the place to be - Emolument says consulting salaries in the Big Four peak at £150k after 15 years, 50% above salaries for auditors.

Not all audit jobs in the Big Four are equal, however. Accounting insiders point out that pay in audit is reflective of the sector you specialise in. If you're auditing charities or the public sector, your pay will be low. If you're auditing banks or TMT companies, it will be higher.

It's also worth bearing in mind that at the very top of the Big Four are thousands of people whose pay is akin to that of the most high-earning of bankers. These are the partners. In 2015, Deloitte's UK partners were paid an average of £750k ($1.2m) each, while partners at PwC, KPMG and EY earned an average of £722k, £715k and £727k respectively. Good money if you can get it. The only problem is that not many ACA-qualified accountants seem to be able to.

Pay for ACA qualified accountants by age