Why it matters

This is not a preference question. It is homework, and one piece of it is worth doing today rather than in 2028.

A necessary caveat: the trip is more than two years out, and entry requirements, fees, and timelines all change. Everything below is what is known now and must be re-checked roughly six months before departure. Treat it as a list of things to track, not a set of instructions to follow yet.

What is known

Passports — the part that needs action now

The Schengen area requires a passport valid for at least three months beyond your planned departure from the area, and issued within the previous ten years. Most travel guidance advises keeping six months of validity as a safety margin, because airlines apply their own stricter checks at the gate and a marginal passport can end a trip before it starts.

Concrete action: check all four passport expiry dates today. Anything expiring before mid-2029 should be renewed well ahead — renewal backlogs are unpredictable, and a passport that expires in early 2029 is a problem for a trip in January 2029 even though the dates technically don’t overlap.

ETIAS — the EU authorization

ETIAS is a pre-travel authorization for visa-exempt visitors, including US citizens. It is an online registration completed before departure, tied to the passport, and valid for multiple entries over a period of years. It is expected to be in force well before this trip.

It is not a visa and does not involve an interview or an appointment — but it does need to be done in advance, and it is tied to the specific passport, so renewing a passport after registering means re-registering. That is an argument for sorting passports first and ETIAS later.

The UK is separate

The UK is not in the Schengen area. Any London leg is a distinct border crossing with its own entry requirements, and the UK operates its own separate authorization scheme rather than participating in ETIAS.

Practically this means: if the itinerary includes London, that is two systems to satisfy rather than one. It is not difficult, but it is easy to overlook when everything else on the trip is a single internal hop. See Which arc? — the northern arc crosses this border, the Mediterranean arc does not.

My recommendation

Do one thing now and defer the rest:

1. Now: check all four passport expiry dates and renew anything expiring before mid-2029.
2. About twelve months out: re-read the current ETIAS and UK requirements, because this is when the details will be settled and reliable.
3. About three months out: complete whatever registrations are then required, after passports are final.

Nothing else here needs a decision. It needs a calendar reminder.

What would change my mind

Nothing — this is the one page on the site that isn’t a preference. The only open variable is whether the itinerary includes the UK, which determines whether we deal with one authorization scheme or two.