Originally Posted by
extreme_panda
Thanks for the info here everyone. I was searching for this exact info!
Planning a trip in August from SFO->LHR->BCN and but the flights are booked on separate tickets. Assuming the rules don't change between then and now, sounds like I still need a COVID test but as long as I don't check luggage, I can stay airside and avoid immigration.
Yes that’s correct for an airside transit. You will need a passenger locator form too.
Bear in mind tho since you are on separate tickets the inbound airline may treat you as an arrival and expect you to comply with all the entry requirements. They are not obliged to treat you as a transit when on a separate ticket or apply the lesser restrictions for that.