The research, which questioned almost 2,000 UK consumers, showed that beef is the most popular roast dinner meat for in both Northern Ireland and the south-west, with 43% of the overall vote.
At 31%, chicken is the most preferred in Wales, while lamb comes out top for people in the north-west, with 26% of the vote.
For all men surveyed, beef leads the way with 42% of the vote, while 32% of women prefer chicken as the meat for their roast dinner.
The research also found that after potatoes, the favourite vegetables to accompany a roast dinner in the West Midlands are sprouts, with 20% of the overall vote. In Scotland, however, it is carrots (also with 20%), while parsnips come out top in the south-east, with 17%.
Susan Gregory, head of food at Maggi, said the research was particularly insightful given that the eating-out sector is due to have its biggest-ever Christmas Day service this year.
Gregory referred to a claim by Bookatable earlier this month that festive bookings for restaurants and pubs have more than doubled over the past few years.
She explained: “Christmas is a key time for pubs, especially those serving food, and the roast dinner remains the favourite meal in the UK.
“Our research has uncovered useful insight that will help pubs deliver a great dining experience to their customers during the festive season.”
The nation’s favourite gravy flavour across all age ranges and gender in the UK was revealed to be beef. Onion was second-favourite with 18 to 24-year-olds (24%), while chicken gravy, at 40%, was popular with those aged between 25 to 34.
Earlier this year, another Maggi survey found that 93% of consumers prefer to pour gravy themselves, and that 83% said they would be more likely to return to a pub if they were allowed to pour their own gravy.
Furthermore, 96% said good gravy was crucial to a roast dinner, while 94% would like to be given a gravy boat for their table when eating a roast dinner at a pub or restaurant.
Following the results, Nestlé launched a Maggi campaign to bring back the gravy boat, which included free PoS kits to pubs.
It claimed the high-value kits, which included 10 gravy boats, have received positive feedback and all the pubs involved have requested more when available.
Gregory said: “If a venue can demonstrate generosity to a customer, then that customer is more likely to score their experience highly in terms of value-for-money, which is a key driver of repeat visits.
“Our aim is to support licensees and chefs in making the most of the enormous festive business opportunity and, crucially, influence and increase repeat visits.
“This can be through using a gravy boat on the table for customers to pour themselves, or creating some festive serving suggestions like using wine, cider, or adding redcurrant jelly or rosemary to your Maggi gravy.”