Spending the night at Madrid airport is not as traumatic as it has several services available 24 hours. While there are hotels nearby, not all passengers are willing to pay for one night when their flight leaves after midnight or early in the morning. While there are air rooms inside the airport, which are rooms with a common living room to take a rest some hours, these are payable. If you are lack of money, you better find another alternative.
The most important thing is that Barajas airport is open 24 hours a day. The T1 is not very comfortable nor does it have so many seats available. While the T2 T3, and T4 have more space and chairs, but not very comfortable. Some banks do not have support arms and those are the ideal to be able to rest on two or three of them. If you observe two or three together without occupying, do not hesitate and occupy them. Take into account that none of the terminals has areas with too much privacy and the lights usually stay on so it is good to wear an eye mask. If you have to sleep on the floor, have a blanket since it is usually cold.
Another option (paying between 20 and 25 euros) is using one of the VIP rooms that are available 24 hours: VIP Lounge Cibeles (for non-Schengen flights) and Amnios Lounge (for Schengen flights). Both have comfortable sofas and showers)
Luggage: The luggage-storage offices (tel.917 466 065) are in T1 and T4, available 24 hours and therefore, if your flight leaves early in the morning you can leave your bags and sleep peacefully without having to watch your belongings and then remove them at the check-in time. The T4 office is on floor 0, in the Arrivals Lobby and, on T1 is on floor 0, opposite the Baggage Room 2, in the garden area. This office provides service to terminals T1, T2 and T3.
Eat and drink: open 24 hours, in Terminal 4 - McDonalds (Floor 2) and in Floor One Door J), Eating Point (Floor 1, Door J).
In turn, there are vending machines with drinks, sandwiches and snacks at all terminals.
Bathrooms: they are enabled although they do not have showers. There are only in the VIP areas and in the air rooms.
WI-FI: Madrid airport has free and unlimited internet access and also wireless access points located in different areas of the terminals. There are also cell phone chargers and printers.
Currency Exchange: available 24 hours
On level -1 of Terminal 4 there are suites from Air Rooms (Tel +34 913 276 015). In the proximity of the enclosure you can find numerous alternatives, many of which provide courtesy transport services for their guests. Ibis Madrid Aeropuerto Barajas (Tel +34 913 010 999), TRYP Madrid Alameda Aeropuerto (Tel +34 917 474 800), Meliá Barajas (Tel +34 902 144 440), Clement Barajas Hotel (Tel +34 917 460 330), Täch Madrid Airport Hotel (Tel +34 913 010 721), Hotel Villa de Barajas (Tel +34 913 292 818), Hostal Viky (Tel +34 913 054 812), Hostal El Príncipe (Tel +34 917 477 965), Hotel Barajas Plaza (Tel +34 913 010 081).