The Bill has been designed to deal with inequality due to race, gender, disability, social class and age. The Government hopes the bill will narrow the gulf between rich and poor in the UK and close the gender pay gap.
But one employment lawyer argues the changes will be "unwelcome" for employers.
Sandra Wallace, employment law partner at DLA Piper, said: "Compulsory gender pay audits come as a costly and unwelcome surprise for businesses that are currently struggling under the weight of the recession. While it is clear pay bias towards men needs to be addressed, companies will now have to make significant financial and legal adjustments to comply with the new regulations.
"Businesses bidding for public-sector contracts will have to ensure they meet strict new procurement guidelines that scrutinise a company's diversity performance. We expect the Equality Bill to bring a sea [of] change to UK business."
The release of the Bill comes amid reports two thirds of businesses are currently not taking any action to address the problem of the gender pay gap.
Sam Mercer, director of workplace business at Business in the Community, said: "Pay inequality between men and women is detrimental not only to women but also society, the economy and individual organisations. In 2009 a person's gender should not have a significant impact on their pay packet.
"Many responsible employers recognise we still have significant progress to make on equality and diversity. In reality, progressive employers concerned with long-term profit and brand value - now more than ever - recognise addressing social injustice and inequality, and promoting inclusion, is to their own advantage."
But David Frost, director general of the British Chambers of Commerce, said: "This Bill will discourage job creation and make employers fearful of the recruitment process. We already know half of small firms struggle to navigate employment law and this will just add to the problem.
"The government commitment not to introduce mandatory gender pay audits until 2013 is not worth the paper it is written on. 2013 does not feature in the Bill itself so the government could easily withdraw this commitment and implement audits much earlier.
"Coupled with the 50 per cent tax rate, this sends a poor message about doing business in the UK."
