The Colemans are in the wealthiest 10% in Britain, with music festivals, mountain-biking and a weekly budget of around £1,800. The Morgans cannot afford festivals with their budget of only £180.
The Gittings family live in a two bedroom ground floor flat in Poole, Dorset. A couple of miles away The Hansens live in a five bedroom property. How will they find living at opposite ends of the wealth divide?
The Llewellyns from Enfield live in a 3-bedroom maisonette and get by on just 97 pounds a week, they swap with the Hornans from Rickmansworth who have a weekly budget of two thousand three hundred pounds.
The Emmotts enjoy a budget of £1300 per week, affording golf, tennis, music and triathlon training. The Blakes have only £125 of disposable income, so treats include walks in the park and film nights at home.
The Lusks, who made their money from the manufacturing industry, swap places with the Bosleys who are used to getting by on less than one tenth of the Lusks' income, brought in by mum Melanie who is a cleaner at a working men's club.
Families from series 2 and 3 reveal what happened when they met for the first time after living each other's lives. Intersperses memorable moments with newly shot footage.
The well-off Hogan family swap places with the less-well-off Buck family for a festive Christmas week at the opposite end of the wealth divide in this Christmas Special edition of the programme.