Employees can request a four-day working week from the first day of their job, but employers are not legally obliged to approve the change, employment experts have said.
The guidance comes in response to a father who wants to reduce his working week from five days to four to help his wife care for their two children.
HR expert Kate Underwood said employees can make two flexible working requests in any 12-month period. The application must be made in writing, dated, and explain the proposed change and when it should begin.
Workers do not have to provide a detailed account of their family circumstances. Childcare can be mentioned, and may help explain the request, but an employer cannot require a full explanation of an employee’s home arrangements before considering it.
Since April 2024, applicants have also no longer been required to set out how they believe the business could manage their absence.
Employers must discuss the request with the employee and make a decision within two months. They can reject it, but only for one of eight specified business reasons.
These include additional costs, an inability to reorganise work or recruit cover, a detrimental effect on quality, performance or customer service, insufficient work during the proposed hours, or planned structural changes to the business.
Underwood advised employees to present the request as a practical business proposal rather than a personal favour. They could explain how their responsibilities would be covered over four days and suggest a three-month trial to test the arrangement.
If the request is refused, employees should ask for the decision in writing and appeal, she said.
Catrin Mills, an employment partner at Sharpe Pritchard, said the law provides a right to request flexible working, not an automatic right to have it granted.
“Your employer must consider the request reasonably and should accept the request unless there is a genuine business reason not to,” she said.
Mills said employers should discuss the proposal with the employee and reach a decision within a maximum of two months. Concerns about customer service, staffing levels, performance and the ability to redistribute work among colleagues could all be relevant reasons for refusal.
Where a permanent four-day week cannot be agreed, employees could propose alternatives such as a temporary arrangement, a trial period, compressed hours across four days or a hybrid working pattern.
