Security guards, nurses, doctors, police and cleaners are among those working on Christmas Day whose monthly pay is less than a decade ago, a new study shows.
The TUC said that apart from kitchen staff, most people having to forego a day off on December 25 have seen their wages fall since 2007 when inflation is taken into account.
The real wages of doctors are down more than £1,000 a month, prison and police officers by over £400, the clergy by £300 and nurses by £100, the union organisation said.
TUC general secretary Frances O'Grady said: "Seasonal goodwill is clearly in short supply on pay day.
"While many of us are tucking in to the turkey, the UK's Christmas workforce will be hard at work keeping vital services running, but their wages are worth even less than they were a decade ago.
"2018 should be the year that the Government finally get wages rising across the UK.
"They can start by ditching their Scrooge-like pay restrictions on our public service workers and by raising the minimum wage."