Previous research from the CIPD, external, an industry body for human resources managers, has indicated that the public sector and charities are more likely to reveal pay information that private firms, while pay ranges were more common than specific salaries.
But it found not all employers were “fully transparent”, with pay ranges sometimes wider than £10,000.
CIPD chief executive Neil Carberry said that while, in principle, giving salary details was “a good thing”, in practice it was “more complicated”.
“There isn’t always a single fixed figure, and employers will want to set pay based on a candidate’s skills, experience and potential.”
Carberry added the process was complex, saying that drafting job adverts is “best left to good employer practice rather than government regulation”.
The government has said it will set out further details on what information will be required and how the legislation will be enforced “in due course”.
Last week, the Equality and Human Rights Commission (EHRC), said publishing salaries in job adverts would be a “positive step”.
It also said bosses should be required to respond to questionnaires about colleagues’ pay to cut pay discrimination.
At present, employers do not have to respond to employee requests for salary information about their co-workers.
The EHRC also said employers should be prevented from asking about current salary when offering a job to stop a history of discrimination from continuing.
Employers in the UK are currently allowed to ask you how much you get paid in your current role, but applicants are under no obligation to tell them.