The UK capital has knocked Zurich off the top spot, with average hotels rates of £126 per night, followed by Zurich with average room rates of £110 per night, and Paris in third place at £106 per night.
HRS analysed bookings made via its HRS hotel portal in 2014, which revealed that throughout the UK and Ireland, average prices for hotels rooms grew steadily in all the major cities in 2014 compared with 2013.
Leeds hotels saw the highest price rise, with an average increase of 21.6%. London followed behind with an average increase of 16.1%, while Birmingham saw an average rise of 14.5%. All UK and Ireland cities recorded an increase in average room rates of at least 9% for 2014.
Edinburgh was the second most expensive UK city, with average rates of £99 a night, while Bristol was third on £87. The city with the cheapest average hotel rate in the UK was Birmingham, at £72 per night.
Jon West, managing director of HRS UK & Ireland, said: "These figures show that UK hoteliers are clearly reaping the rewards from an uplift in demand from both leisure and business travellers. This is great news for hoteliers who are able to charge more on average for their rooms per night, but obviously not so great for guests paying a premium.
"In fact, as rates continue to increase in the UK and Ireland, and fluctuate globally, we really would urge travel and procurement managers to review the effectiveness of their travel programmes on a regular basis to ensure they’re getting the best rates possible to make substantial savings for the long-term."
Worldwide, New York was the most expensive city for an average night’s stay at £157 per night, followed by Washington (£130) and Rio de Janeiro (£128).
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