Air Travel Organisers' Licensing (ATOL) is a United Kingdom Civil Aviation Authority (CAA) scheme to give financial protection to people who have purchased package holidays and flights from a member tour operator.

The majority of UK tour operators are required to hold an ATOL licence, without which they may not legally sell air travel. ATOL-licensed firms will have had their business practices inspected by the CAA. An ATOL licensed tour operator must also obtain insurance bonds from the CAA. The aim of this is to provide refunds to travellers affected by any event which causes the airline to be unable to provide travel for its customers, and to arrange for flights (in addition to accommodation and other items which may be included in a package holiday) to return home those already abroad at the time.

In the 1960s, voluntary organisations such as the Association of British Travel Agents (ABTA) provided a degree of financial protection for air travellers. In 1970, the Federation of Tour Operators (FTO) (then the Tour Operators Study Group) introduced a bonding scheme whereby their members had to obtain bonds to the value of 5% of their annual turnover. In 1972, ABTA followed suit.

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