The airlines that have mastered the art of low-cost travel are undoubtedly European budget airline giants like easyJet and Ryanair. While in the United States, budget airlines may reduce ticket prices by 20% to 30%, a ticket in Europe can drop to as low as a quarter of a traditional ticket on a full-service network carrier.

This has become painfully true on routes across the continent, so much so that even budget-conscious students can afford to take regular hops on these airlines to go from city to city. Europe is not packed with any fewer destinations, nor are passengers any less affluent than in the United States.

Fares, however, remain painfully higher than those across the Atlantic. For a resident of Lisbon, Portugal, in search of a pleasant weekend of skiing in the Swiss Alps, a flight to Geneva, a city within striking distance of many of Europe's best ski resorts, can go down to as little as around $35 roundtrip on easyJet.

Between Houston and Denver, an excellent stopping-off point for most Colorado resorts, the cost of a roundtrip ticket on Frontier Airlines, the cheapest option on this route, is $130. In this article, we will look at five key reasons budget airlines have lower fares in Europe.