Up to 9.6 million UK workers are to benefit from the changes to sick pay rules, according to unions. They say the policy has widespread support from voters despite pushback from some businesses.

From Monday, about 8.4 million workers who rely on statutory sick pay – the minimum amount employers must pay – will be paid from the first day of becoming ill rather than from day four, according to an analysis by the Trades Union Congress (TUC).

Meanwhile, 1.2 million workers, who were previously not entitled to statutory sick pay because they earned below the £125-a-week threshold, will become eligible. This move will disproportionately benefit women, who are overrepresented in lower-paid jobs and part-time work, as well as disabled employees and younger and older workers.

The TUC said it would remove the pressure on lower-income households, who have had to choose between potentially spreading and prolonging their illness or losing much-needed pay.

The changes are part of the first tranche of rights being provided through the Employment Rights Act 2025, which is also introducing new protections regarding sexual harassment, parental leave and trade union recognition.

The Labour government’s policy has proved popular across political lines, with 76% of those surveyed by the TUC saying they support workers having sick pay from day one.

That is despite growing frustration among some employers, who are warning that the new sick pay rules and wider Employment Rights Act are putting pressure on already stretched balance sheets.

Neil Carberry, the chief executive of the Recruitment and Employment Confederation, said businesses were already grappling with increases to the national minimum wage, payroll tax hikes, and now energy price rises sparked by the war with Iran.

He said the pressure was already forcing bosses to cut back on staff and raise prices to make ends meet. “We are at a tipping point,” Carberry said. “The changes to statutory sick pay introduced this week will also cause chaos if not coupled swiftly with better guidance for firms, as a small minority of workers will try to defraud firms.”