United Airlines' online check-in procedure : "stay" or "transit" for one night?

I have booked flights which involve me transiting through the USA (Newark) en route to Costa Rica. My itinerary includes an overnight stay in New York; I'll be spending the night with relatives.

I went through United Airlines' online check-in process and I was asked if I was travelling to the USA for transit or if I would be staying. (I imagine I'll be asked a similar question at the immigration desk when I arrive in Newark.)

As a UK citizen, I already have an ESTA through the Visa Waiver Program; this question is not about visa requirements.

Which box should I tick? Am I transiting, or staying?

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How many hours can you check-in online before a flight?

Most airlines permit online check-in up to 24 hours before departure. The earlier you do so within that window, the better\u2014because you'll have more available seats to choose from.

What do you do when you check-in online for a flight?

To check in for your flight: Visit your airline's website as soon as 24-hours prior to the departure of your first flight. Use the confirmation number in your online account to check in. You will also be able to view your seats and, if permitted by the airlines, confirm your seating preferences.

Does it matter when you check-in for United?

Check-in is available starting 24 hours before your scheduled departure. Required timing for check-in, baggage check and boarding may vary based on your departure airport and destination. See our Check-in and Airport Processing Times page for details.

What is United check-in policy?

For most United- and United Express-operated flights within the U.S., travelers with checked baggage must check in at least 45 minutes before departure.

UNITED AIRLINES - Watch this before you fly them.

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