The UK has already experienced five heatwaves this year, and with more forecast, one thing is certain: sweaty commutes and stuffy offices are here to stay. 

Deciding what to wear to work during the summer can be surprisingly difficult. Will you be judged for dressing too casually, showing too much skin or appearing unprofessional? 

So, what is acceptable to wear to work over the summer months and can your employer tell you what to and what not to wear? 

As employers continue to navigate employee wellbeing, flexible working and evolving workplace expectations, dress code policies are increasingly coming under review. HR teams are tasked with striking the right balance between allowing employees to stay comfortable during periods of hot weather while maintaining a professional and inclusive workplace. HR technology supports HR teams by helping them update their organisational policies, communicate these updates with staff and make dress code policies as easily accessible as possible. 

According to UK law, dress codes can be a legitimate part of an employer’s terms and conditions of service, and dress polices for men and women don’t have to be identical. However, the standards should be equivalent, and any less favourable treatment based on sex could be direct discrimination. Dress codes must not lead to harassment at work by colleagues or customers, so any requirements for employees to dress provocatively is unlawful. 

This issue gained national interest in 2015 when receptionist Nicola Throp was sent home for refusing to wear high heels. Her subsequent petition attracted more than 150,000 signatures and prompted a report by two parliamentary committees into discriminatory workplace dress codes. 

The report concluded that while the Equality Act 2010 should ban discriminatory dress codes, in practice the law wasn’t applied to protect workers of either gender. It also found that discriminatory dress codes remain widespread; they even found cases where women were required to wear revealing outfits, dye their hair a certain colour and to reapply makeup constantly. Finally, the report called for the government to review the law and to make changes where necessary to ensure it is more effective in preventing discriminatory dress code policies. 

Looking beyond the UK, employers in other major cities are also reconsidering traditional workplace dress codes in response to increasingly hot summers. This year, the Tokyo Metropolitan Government is pushing employees to lose the usual suit and tie for a more casual look featuring t-shirts, shorts, and trainers. Governor Yuriko Koike introduced the policy in April, as part of a summer tradition that seeks to reduce air conditioner use to preserve electricity. However, the office policy is receiving some mixed reviews. While many employees welcome the relaxed dress code, others argue it highlights a double standard, with women still expected to wear tights when their legs are visible.  

A recent poll by market research firm Ipsos found that 62% of people thought it was acceptable for men to wear shorts to work and 63% found it acceptable for women during the hot weather spells. Fashion designer Amanda Wakeley says, “we’re not talking about short-shorts or denim hot pants, if you’re asking yourself whether they’re too short, they probably are.” Wakeley goes on to say that “shorts are the trickiest item to get right in a professional environment” and recommends tailored, knee-length shorts for both men and women, arguing they strike the right balance between staying cool and maintaining a professional appearance.  

Ipsos’ research also found that 64% of the public see flip-flops as unacceptable footwear for men in the office, compared with 58% for women. Amanda Wakeley says that “flip-flops give the instant signal of leisure rather than professionalism and can make polished outfits look underdressed.” Clare Chambers adds that “even during the hottest weather, espadrilles are the better option as they’re breathable while still covering the foot.” For HR leaders, these changing attitudes reinforce the importance of having clear, consistent dress code policies that reflect modern workplace expectations while avoiding ambiguity during periods of extreme heat. 

Casual work attire doesn’t necessarily mean anything goes. While some workplaces are embracing a more relaxed dress code for the warm summer months, experts still advise against clothing designed for leisure rather than work. Kit Swann, Fashion Editor at MR PORTER has said “you should keep the licensed sportswear out of your workplace (unless you work in a sports club), as football shirts stand for passion and a different kind of professionalism.” He continues, “the technical fabrics most kits are made from are designed for mobility and temperature regulation,” which might be handy if you work in an office without air conditioning during the summer months but “if you’re likely sat at your desk in your air conditioned office, not running back and forth, then a good cotton shirt will serve you just as well.” For HR teams, this highlights the challenge of creating dress codes that allow employees to express their individuality while maintaining standards appropriate for the workplace. 

Heatwaves and changing employee expectations are prompting many employers to rethink traditional dress codes. Rather than relying on unwritten rules, organisations are increasingly reviewing policies to ensure they are gender-neutral, inclusive, and flexible enough to accommodate warmer weather for all, while maintaining appropriate standards for client-facing and office-based roles. 

Summer office wear isn’t about fashion. It’s about creating clear expectations that balance employee comfort with organisational professionalism. As workplace norms continue to evolve, HR leaders should regularly review dress code policies to ensure they remain inclusive, practical, and aligned with today’s flexible ways of working. HR technology can also support employers by helping them manage, update, and communicate dress code policies through self-service portals, intranets, and HR platforms, ensuring employees have easy access to the latest guidance during periods of extreme weather.