The index ranks 150 global cities based on an average prices across, hotel, hostel and Airbnb accommodation.
It found that London beat Paris, Amsterdam, Sydney and Hong Kong in the world rankings, and came out top in the UK.
Liverpool was the second most expensive city in the UK and the 18th in the world, while Aberdeen came in at number three in the UK and 27th in the world.
London is particularly costly when it comes to hotels, with the city ranking 15th most expensive for a 5 star hotel and 13th most expensive for a 1-4 star hotel. Liverpool ranks 19th in the 1-4 star hotel index, with Dublin also making it into the top 20.
Aberdeen, meanwhile, is the 5th most expensive city for hostels, behind New York, Miami, Zurich and St Moriz.
For an Airbnb room, Aberdeen ranks 6th most expensive in the world, followed by Newcastle in 7th, Birmingham 11th, Bristol 12th, and London 15th.
GoEuro.co.uk compiles its accommodation price index to understand the effect of new trends in accommodation on the hotel industry.
For the full ranking and data, click here: http://www.goeuro.co.uk/accommodation-price-index.