The survey of HR professionals found 51% of organisations have never completed an equal pay audit.
Over a third (36%) had completed one in the last year, and 7% had completed one in the last three years.
More on the gender pay gap:
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Jemima Olchawski, chief executive of gender equality charity the Fawcett Society, said while reporting on the gender pay gap is a legal requirement, employers should go further to find out what is causing it.
Speaking to HR magazine, she said: "Pay gaps will only be closed when employers understand why they exist and commit to acting accordingly.
“Pay audits are a key part of the picture and it's disappointing that over half of the organisations polled have never carried one out.
“We need all employers to to get to grips with and take action on their pay gaps - and this isn't just the gender pay gap.
“We know that the ethnicity pay gap unfairly impacts women from Black and minoritised backgrounds.”
Only 12% of survey participants said they publish salary ranges for employees to see.
Of those who said they do not publish salary ranges, 27% said their framework was under development, 15% were concerned about potential reactions and 11% said it was not a priority.
Rameez Kaleem, founder and managing director at 3R Strategy, said pay transparency would help encourage equal pay and improve employee relations.
Speaking to HR magazine, he said: "Pay transparency isn't about publishing salaries, but it's about being clear and open about how we make pay decisions.
“When we're transparent about our pay processes, there is a greater emphasis on fairness and equity.
“It gives employees reassurance that they're being treated fairly and not being undervalued or discriminated against.”
Companies’ reasons for not publishing salary ranges included that effective communication was needed before sharing (16%); there was not enough confidence that current ranges are right for the organisation (11%); they had concerns about equal pay (10%), and that salary ranges were not implemented in the company (17%).
Kaleem said HR teams need to use a consistent structure when determining pay or risk worsening pay gaps.
“HR teams can make sure that they have pay and reward processes in place that ensure fairness and consistency.
“This means participating in salary surveys, having an approach to job evaluation, and setting up their own pay structures. You can only carry out an equal pay audit through job evaluation so having some approach to this is critical.
“Finally, while carrying out equal pay audits isn't a legal requirement, it is recommended that one is carried out every three years to make sure that there are no equal pay risks and if there are – they can make the necessary adjustments.”
