The most cost-effective multi-stop route between South America and the UK

Q&A: Travel unravelled

Q. My parents-in-law will be visiting us from Chile next year, flying from Santiago (pictured) in June. Ideally they would fly via Spain, as that helps in terms of both language and travel time. They will also be travelling to Europe, certainly to Rome. Any pointers for getting the best-value flight? Should they take the return flight from outside the UK to avoid the air tax? Denis Fitzpatrick, Dunstable

A. Let’s start with the long-haul stretch, to Europe. Cheap round-trip deals from Santiago are available travelling by both the US and Canada, on airlines such as American and Air Canada. But the journey via Madrid is much shorter and only slightly more expensive.

Iberia, of Spain, is the leading carrier across the South Atlantic. However, in my experience, inflight comfort and service is better on the Chilean airline, Lan. Like Iberia, Lan is part of the Oneworld alliance, which means you can connect easily with British Airways between London and Madrid.

Next, as you surmise, the overall fare depends on the route they take back to South America. Air Passenger Duty (APD) will be £94 by then (it’s £92 now) if they fly home direct from the UK with only a change of plane in Madrid. They can save more than £80 each in APD if they depart from somewhere other than Britain. The way to do this is to put the Rome element at the end of the trip, and for them to fly back from Italy. Then, their APD liability will be only £13 each for the hop to Rome.

BA’s useful “multi-stop” facility on  ba.com quotes a fare of around $1,770 (£1,090) for a June trip that goes Santiago-Madrid on Lan, Madrid-Heathrow on BA, Heathrow-Rome on BA and the same in reverse. The crucial thing is to make sure that the Rome-London-Madrid-Santiago journey does not involve a stopover of 24 hours or more in London – which would make it liable to APD and raise the fare.

One of the connection possibilities at Heathrow allows a stopover of five hours – so you could arrange to see them once more before they return home. Fares for the summer are likely to increase, so best book now to lock into a reasonable deal.