Televised football matches will be kicking off at various times throughout the tournament, which begins on Thursday, starting as early as 11am.
However, the TUC said more than one in four UK employees – or 5.7 million people – work nights, and many of them will also want to watch the matches.
The TUC said bosses should talk to their employees in advance about arrangements for key games and arrange for staff to watch the game on the company’s premises, if appropriate. In other cases, staff should be allowed to work from home or work flexibly to allow them to follow the football. Companies have been directed to “be as flexible as possible with annual leave requests”.
TUC general secretary Frances O’Grady said: “The World Cup is a landmark sporting event. Millions of workers around the UK will want to cheer on their national teams.
“Tournaments like this can be a great for building camaraderie at work, with colleagues running sweepstakes and spending time together.”
Ms O’Grady, who supports England and Arsenal, added: “It’s important employers do not score an own goal by acting like killjoys. To avoid problems they should try to let people who want to watch the games do so, either at work or at home – and then claim back their time afterwards.
“Whether it’s major sporting events like the World Cup or watching your kids take part in their school sports day, allowing people more flexibility in how and when they do their work makes them happier and more productive. Come on England.”