The answer to this question depends on where you are flying from and to, as well as which airline you are flying with.

Flight:  Non-Schengen — Madrid — Non-Schengen

Whether you need a visa in this case depends on the airlines and whether you bought a through ticket (single) or combined flights from two airlines yourself.

Countries that are part of the Schengen Agreement include: Austria, Belgium, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden, Switzerland.

You are flying with one airline or two airlines that are part of the same alliance

For example, Moscow — Madrid — Punta Cana (Iberia). In this case, your arrival and departure will be from the international flights terminal  — T4S, where there is a transit zone where you can stay for up to 24 hours.

However, there are exceptions to this rule, for example, if you arrive in Madrid from London. The UK and Ireland are not part of the Schengen Agreement, but for EU citizens, these flights are still considered domestic, so arrival and departure to London take place from the domestic flights terminal — T4.

What should those do who are flying to Madrid from London and then to a non-Schengen country?

As a general rule, in this case, you need a visa. However, if the flight is operated by British Airways, the plane arrives at a special gate where transit passengers without Schengen visas are met and transported to terminal T4S, so you do not go through passport control and do not need a visa.

You are flying with two different airlines that are not part of the same alliance

In this case, arrival and departure will most likely be from different terminals. For a layover in Madrid, you will need to collect your luggage, transfer from one terminal to another, and check it in again, for which you will need a visa.

— Terminal T1: Air Europa, Delta Airlines, Egyptair, Turkish Airways, Аэрофлот;

— Terminal T2: Aegean, Air Europa, Air France, KLM, Lufthansa;

— Terminal T4: American Airlines, British Airways, Iberia, TAM Airlines and US Airways, S7, Трансаэро, МАУ.

For example, for a transfer from T1 to T4S, a visa is required. If you do not have a Schengen visa, you will not be allowed to board the flight.

Flight: Schengen — Madrid — Any country

For example, Rome — Madrid — Moscow, you already have a visa, as you already obtained a Schengen visa to visit Rome, and you do not need to obtain any additional visas for a layover in Madrid.

Flight: Any country — Madrid — Schengen

For example, Moscow — Madrid — Lisbon. To visit Lisbon, you should already have a Schengen visa, and you do not need to obtain another one for transit through Spain.

If you have a Schengen visa and the layover time allows, you can easily leave the airport and take a walk around the city or stay overnight in a hotel during a night layover.

• T4S  → T4S — no visa needed

• T4S  → T4 — visa needed, with the exception of British Airways/Iberia flights from London

• T1 → T1 — no visa needed if you don't need to collect luggage. Otherwise, you will have to leave the terminal and then re-enter, for which a visa will be required

• T1 → T4S — visa needed

• T1 → T4 — visa needed