Dual UK/US-nationality & APIS

I'm now a dual-national (UK/US). Might any v-flyers out there know which passport information I should use for APIS?

I must use my US passport to enter the US, and my guess is CBP would want me to use it when leaving. Although not so rigid about regulations, it would make sense to use my UK passport to enter/leave the UK.

So on a US-UK flight, which APIS data should I input? It says use the data from whichever passport I am using, but I'll be using both.

My son has dual UK/US nationality on the APIS i always put the U.S. passport from the U.K. to U.S. then the same returning to the U.K.
Check in with the U.S. passport at the airport then arriving in the U.K. go to the U.K. border control with the U.K. passport he has never had any issues.

Brilliant, thanks Las56.

My sister has dual UK/US nationality. Back in the days of outgoing border control in the UK, she made the mistake of presenting her US passport at the desk. The officer was flicking through it looking for a UK Visa & asking her how long she had been in the UK etc. She then pulled out her UK passport and all was fine.

If you have two passports, ask the VS check-in agent to "security sticker" both on the back. Again my sister has had problems when she's presented her US passport at check-in (as you have to travel to the USA on this one) and then mistakenly pulled out the UK one at the boarding gate [minus the security sticker]. NB: This was when they actually asked the security questions, they don't seem to bother now, but still sticker the passport.

You have to enter the USA on the US passport, as they will not admit you in under the Visa Waiver Program under any other passport if you are a US Citizen (or dual-national). Unsure if they track US citizens leaving the country the way they do people on VWP entries. I suspect they don't as you have a legal right to be in the USA, live there and work there & stay as long as you want.

Definitely enter the UK on the UK passport though - it could save you quite a bit of time in the immigration queue (but nothing like the time saving a US passport makes in a US immigration queue though!)

Thanks, Kraken, and - as Las56 does for his son - does your sister always use her US passport details for APIS (in both directions of travel)?

Thanks, Kraken, and - as Las56 does for his son - does your sister always use her US passport details for APIS (in both directions of travel)?

Yes, she enters her US passport details for APIS (as the airline by default uses the outbound details for the inbound flight). On arrival back in the UK she just uses her UK passport on the e-gates / immigration desks. The UK are not quite as paranoid as the USA on knowing the address of your first nights stay / other APIS details. A valid UK passport will get you through no problem.

It's often been the case when arriving back in the UK that the "Rest of the World" queue is considerably shorter than the "UK & EU" queue...

Looks can be deceptive though - there'll often be far fewer people in the queue but it can move a lot slower as each person can take several minutes to be processed instead of the 20 seconds or so it takes for the average UK/EU national.

Thanks, Kraken, and - as Las56 does for his son - does your sister always use her US passport details for APIS (in both directions of travel)?

Yes, she enters her US passport details for APIS (as the airline by default uses the outbound details for the inbound flight). On arrival back in the UK she just uses her UK passport on the e-gates / immigration desks. The UK are not quite as paranoid as the USA on knowing the address of your first nights stay / other APIS details. A valid UK passport will get you through no problem.

Brilliant, thanks Kraken.