The trade union's call for employers to be obliged to publish these gaps comes as a new TUC analysis showed that the average pay gap for disabled workers has hit 15.2% – the equivalent of £2,821 a year. For people with mental illnesses and depression the pay gap is even worse, at 29.8% and 26.3% respectively.
Last week ministers published a voluntary code to encourage employers to disclose the number of disabled people they employ, their career progression and pay.
But the TUC said that without a legally-binding requirement on companies to publish their pay gaps (and set out what action they are taking to address them), progress will be slow.
The union said that far more needs to be done to remove the barriers facing disabled people in the workplace. Just half (50.5%) of working-age disabled people in the UK currently have a job compared to four-fifths (81.1%) of non-disabled people, its research highlighted. Meanwhile, just three in 10 (30.4%) people with a mental health disability are in work.
The TUC has called on the government to introduce a statutory requirement for employers to report on their disability pay gaps and employment rates, and to publish action plans setting out how they will address discrepancies.
TUC general secretary Frances O’Grady said that a "light touch" will not be sufficient in tackling the challenges facing employees with disabilities: “Disabled people face the double whammy of poorer job prospects and lower pay. Paying lip service is not going to fix the problem.
"Employers must be legally required to publish their disability employment and pay gaps. A light-touch voluntary approach simply won't cut it. Large companies have to report their gender pay gaps. Disabled people deserve the same level of transparency.”
Commenting on the Department for Work and Pensions launch of voluntary reporting, CEO of the Business Disability Forum Diane Lightfoot said that she welcomed the government’s decision, but that the gap is "complex" for those who may not identify as disabled. “We welcome a focus on disability and mental health as logical and necessary priorities alongside reporting on gender and other protected characteristics, and particularly as a tool in helping to close the disability employment gap,” she said. "However, measuring this gap is complex; many disabled people may not identify as such or may not have shared their disability with their employer.”
Encouraging a culture where employees can speak openly about their disability is vital, she said: “Many of the queries we get to our advice service are around how organisations can encourage employees to talk about their disabilities or long-term conditions and to ask for the support they need.
“This requires the development and nurturing of a supportive culture where employees believe that the benefits of talking about their condition outweigh the perceived risks. Only then will we see reliable figures about these three important topics.”
Lightfoot added that career progression is another difficulty for those with disabilities. “We also know from our own research that there is too often a gap between the career progression of disabled people, including people with mental health conditions, and that of their non-disabled peers. It is vital that this is addressed as part of creating a truly inclusive workplace,” she said.
"Only once disabled employees feel able to talk freely about their condition will we be able to have a truly meaningful measure of disability at work, and to start shifting the dial in creating an equal workplace for all.”
Speaking to HR magazine, Simon Morris, HR director of DDD group, added that reporting on disability pay gaps is only part of the solution: "The analysis conducted by the TUC raises a really interesting but concerning issue, and it is disappointing to see such a disability pay gap still in existence in 2019. The gender pay gap issue has shown that tackling issues like this are sometimes complex to solve. Whilst reporting on disability pay gaps may be a part of solution, changing behaviours will require all stakeholders to work together in different and new ways," he said.
"Only by bringing together all stakeholders (government, trade unions, industry, charities etc.) can we start to make progress and start to create equality for all employees – irrespective of gender, race, background or disability status."
