Sofia in Bulgaria offered the best value among 49 world cities for those wanting a one-night stay in a four-star hotel with meal and cocktails for two, the figures from TripAdvisor showed.
Including a return taxi trip, a Sofia one-night stay for two people cost £104, while a similar stay in the most expensive location surveyed - Oslo in Norway - was as much as £381.
London was also one of the most expensive locations, where a hotel stay plus taxi, dinner and cocktails cost £296.
For the purposes of the cost-comparison table, the taxi trip was based on two journeys of two miles each. On this basis, taxis cost £27.20 in London but just £1.39 in Kuala Lumpur in Malaysia.
After Sofia, the next least-expensive hotel destination was Hanoi in Vietnam (£115), followed by Warsaw in Poland (£123), Sharm el Sheikh in Egypt (£125.45) and Budapest (£127).
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London was the seventh most-expensive city in the table but this was an improvement in affordability terms, as the UK capital topped the table for the costliest destination in last year's list.
TripAdvisor spokesman Angus Struthers said: "The list shows that Asia is the most affordable continent, while Europe is the most expensive, but some European cities - like Sofia, Warsaw and Budapest - are bucking this trend."