Madrid Transfer from T4 to T4S with liquids/duty free
 

I am flying from LGW to MAD T4 transferring to T4S and Iberia Long-haul. Can I buy duty-free liquids at LGW and take them onto the long-haul flight out of T4S?

Yes. You do not even have to go through security at MAD.

That's interesting as last time I transferred from T4 to T4S I had both a passport and hand baggage check (which is why I have asked)

That sounds like a T4S to T4 change which would involve security.

You will have the option to disembark from the rear and take a bus to T4S from the LGW gate where you will be deposited into the departures area directly or if you feel like walking a bit between flights you can go through two separate passport controls, but no security and walk the terminal to the train back to T4S.

Are you suggesting there is a bus that takes you from Airside T4 to Airside T4S? I have done this at Chicago and it avoids all the security and passport controls. That would be great if there is something like that at MAD

Yes.

All (except the IB and BA rotations to LHR that use big birds) flights from UK and Ireland arrive to the H gates in T4, which is the special non-Schengen area for that flights. Then the crew will direct you to the bus or someone will be waiting outside to take the transit passengers and you will be dumped into the departures area of the T4S. So no security, no passport control.

Many thanks for clarifying!

Yes, you disembark from the main door as usual, and half way up the jetbridge there will be someone from Iberia saying "tránsito" and guide you down steps to a bus. This takes you straight to T4S departures.