The regional plan borders that surprise travellers

European regional plans are typically built around the European Union plus a familiar handful of neighbours, which means the edges are where the surprises live. Switzerland and Norway are outside the EU and are sometimes outside the plan. The United Kingdom's inclusion has been inconsistent since it left. Turkey straddles the boundary in every sense and is frequently priced as its own region. Russia, Belarus, and Ukraine are usually absent for reasons unrelated to geography.

The smaller entries catch people out more often than the large ones. Andorra, Monaco, San Marino, the Faroe Islands, Gibraltar, and the Channel Islands each have their own operators, and a plan covering the country that surrounds them does not necessarily cover them. If your route touches one, check it by name.

An Asian regional plan is usually East and Southeast Asia. Central Asia, South Asia, and the Middle East may each be a separate region or absent entirely, so a trip from Bangkok to Kathmandu to Dubai can cross three commercial regions without leaving the continent. India in particular is often its own tier, and mainland China is almost always treated separately.

The Middle East and North Africa are sometimes bundled and sometimes split down the middle. Israel and the Gulf states are frequently priced apart from the rest. None of this is arbitrary from the operator's side — it reflects who has agreements with whom — but it is invisible from a region name on a product page.

North America usually means the United States and Canada; Mexico is sometimes included and sometimes not, and the Caribbean is almost always separate. Latin American plans vary widely in whether they reach Central America, and territories such as Puerto Rico or the French Caribbean often follow the operator of the mainland they are administratively attached to rather than the region they sit in.

Africa and Oceania are the regions where the country list is most worth reading in full. Coverage is real but uneven, and a plan can include a dozen countries on the continent while missing the two you are visiting. The same applies to island destinations everywhere: they are frequently their own operator and their own line item.