Connections in Lisbon and Madrid for a Schengen flight - is 1hr too short if I don't have an EU passport?

I have two potential flights from Porto to Naples and I'm trying to see if the layovers are too short.

The first option is on TAP Air Portgual from Porto to Naples via Lisbon. I have a 55 minute layover.

The second option is on Iberia from Porto to Naples via Madrid. I have 1hr 20 minutes there.

I do not have an EU Passport (I have a US one). Do I have to clear customs/immigration if I'm flying within Schengen countries? Are these layovers too optimistic?

If none of these work, I have to do a 1.5hr layover in Frankfurt and I know that will be a challenge, so I'm trying to avoid it.

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Connections in Lisbon and Madrid for a Schengen flight - is 1hr too short if I don't have an EU passport? - Bridge during Nighttime

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Connections in Lisbon and Madrid for a Schengen flight - is 1hr too short if I don't have an EU passport? - Flight Schedule Screen Turned on

Do I have to go through immigration for a connecting flight in Lisbon?

You have to go through passport control. I am travelling within the Schengen area or on a domestic flight. No procedures are required. Just head to the boarding gate of your next flight.

Do I need a passport for a connecting flight?

Catching a connecting international flight in the U.S.? International travelers connecting through a U.S. airport are required have a valid passport and visa for the U.S., and may need a visa for their final destination.

Is 1 hour layover enough in Lisbon?

Re: Is 1 hour 10 minute layover in Lisbon enough time? Yes if TAP sells you a ticket with a 1hr 10 minute connection then it's their problem if it's missed because of a delay to the first flight - unless of course you manage to get lost in the airport. Luggage must be checked through and the transfer done airside.

Do I have to go through security again for connecting international flight?

Yes, a security check is mandatory when you take a connecting flight. This is because there is a time lag between getting off one aeroplane and getting on-board another to reach your destination.

Do's and Don'ts in Connecting Flights | Points to Remember

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