SCORES of Scottish firms are each facing thousands of pounds in fines by not disclosing their gender pay gap figures by tonight’s deadline.

By midday on Tuesday, it was estimated almost 1,500 firms across the UK required to register their pay gap numbers still had not done so, including many believed to be from north of the border.

At midnight Wednesday an estimated 9,000 companies and public bodies with 250 employees or more must have submitted their median and mean gender pay gap data to the Government Equalities Office or face an unlimited fine.

By the earlier deadline of Friday March 30, some 97 per cent of public sector businesses, including schools, universities and hospitals, had reported their data.

READ MORE: Theresa May vows to tackle ‘burning injustice’ of gender pay gap

Amber Rudd, the Home Secretary and Minister for Women and Equalities, said: “There is absolutely no excuse for businesses in the private sector not to be transparent about their gender pay gap before the deadline set down in law; particularly after the public sector showed such a strong reporting performance.

“Businesses should see reporting gender pay gap data as just the first step on the road to creating fairer and more equal workplaces across the UK. They should be putting action plans in place to break down the barriers to women’s progression in their organisations.

“Closing the gender pay gap also makes economic sense. Research shows that improving women’s participation in the labour market could add £150 billion to the economy by 2025. That’s a number we cannot afford to ignore,” she added.

Carolyn Fairbairn, Director-General of the CBI, said: “Gender pay gap reporting is an opportunity for businesses to drive change in their workplaces. For the first time, every larger firm will know the average pay difference between men and women in their company. And what gets measured gets changed - helping to develop more inclusive workplaces and support more women into senior roles.”

Home Office sources made clear that once the deadline had passed, it would reveal the number and names of those companies, which had failed to comply.

The gender pay gap is calculated as the difference between the average salaries of men and women; it is not the same as equal pay, where firms are required to pay people doing the same job the same salary regardless of gender.

The national median gender pay gap is 18.4 per cent.

Ryanair is the best-known company in the top 10 of those with the worst gender pay gap. The airline pays women 71.8 per cent less than men on average; when comparing median hourly rates, for every £1 men earn, women earn just 28p.

READ MORE: Theresa May vows to tackle ‘burning injustice’ of gender pay gap

The airline stressed the disparity was due to the number of UK pilots it employed: 546 are male and only eight are female.

According to the UK Government’s website, the median hourly gender pay gap figures where men earn more than women include -

*Aberdeen Asset Managers Limited: 37 per cent;

*Royal Bank of Scotland PLC: 36.5 per cent;

*Glasgow Prestwick Airport: 22.1 per cent;

*Scottish Power UK PLC: 21.9 per cent;

*Diageo Scotland Limited: 16.7 per cent and

*The National Library of Scotland: 0 per cent.

Baroness Brady, the famous businesswoman, who is vice-chairman of Premier League football club West Ham United, said more women needed to "rock the boat" if they were to achieve equal pay with men.

The Conservative peer, who presented a Channel 5 documentary titled Why Do Men Earn More Than Women, said: "There's an issue that women have this fear factor where they don't have the confidence to ask and they are sort of grateful for the job and do not want to rock the boat.

"But we need to get more women rocking that boat."

Lady Brady, who also stars on The Apprentice alongside fellow peer Alan Sugar, told ITV’s Loose Women programme that just seven per cent of women negotiated a pay rise compared to 57 per cent of men.

She also said the majority of women accepted a job before asking what it paid while men tended to ask what the salary was before accepting it.

"So there's something to do with attitudes...about confidence...about demanding what you are worth."

READ MORE: Theresa May vows to tackle ‘burning injustice’ of gender pay gap

The mother-of-two said since making the documentary she believed the biggest barrier to equal pay was motherhood.

"When you have a child you have to come out of the workplace. In finance, women are paid 40 per cent less than men because of these career gaps they have to take.

"The biggest barrier to women who have children and want a career is high quality, affordable childcare and that is a real problem we have to solve in this country, so women can get back into the careers they want."