The company says the rate of restaurant insolvencies reached record levels in the first quarter of 2009 and the figure is expected to peak again in early 2010.
The overall rate of restaurant insolvencies from January to September was 25% higher than the same period in 2008.
PWC now predicts that restaurants could face their quietest Christmas since the 1990s as both public and private sectors squeeze their spending.
PWC hospitality & leisure director Stephen Broome said: "Despite the descent into technical recession, this time last year many corporate Christmas lunches had already been booked, deposits taken, and to cancel would have meant letting staff down. However, faced with the economic realities of this recession, company bosses have now had nine months to refine policies and prepare staff for more restrained celebrations this Christmas."
He suggested that restaurants should develop special offers to tempt employees into celebrating at their own expense.