There has been a big jump in the number of people working on Christmas Day, according to a report by the union organisation the TUC.
It found that hospitals and hospitality were among the sectors asking more staff to forego festive breaks.
The TUC said almost 172,000 workers were on duty on December 25 in 2010, a 78% increase compared with 2004.
There were equal numbers of men and women going to work on Christmas Day, with those in the NHS and social care making up the biggest group.
In total, 74,521 were on duty in that sector on December 25, 2010 - the last Christmas the figures were available for.
Its study found there was also a big jump in the number of people working in hotels, pubs and restaurants, hitting just over 14,000.
TUC policy officer Paul Sellers stressed that those working over Christmas should be well treated to keep morale high.
"The old 40-hour, five day week has got a bit fuzzy - people are increasingly working at weekends, they're working in the evenings and bank holidays," he told Sky News.
"We should be grateful that people are working on Christmas day, when, for example, we want to go to a restaurant, or we need healthcare.
"But what we need to do is make sure they're properly treated, either through pay or some other way."