What documents do I need to travel from the US to the UK?

What documents are required for traveling from the US to the UK?
I’m flying out tomorrow night and just realized a few hours ago that I needed an ETA, which thankfully got approved right away. It’s been a bit of a panic, and now I’m worried there might be other requirements I haven’t considered. I have my passport, ETA, and a doctor’s letter for my medications. Do I need to provide any proof of vaccinations? Is there anything else I should be aware of?
When traveling from the US to the UK, your primary documents include:
As for additional requirements:
Proof of Vaccinations: Currently, the UK does not require proof of vaccinations for entry from travelers coming from the US. However, it’s a good idea to check the UK government’s official travel advice closer to your departure date, just to make sure there haven’t been any last-minute changes.
Travel Insurance: While not a requirement for entry, it’s highly recommended to have travel insurance in case something unexpected happens.
Return Ticket: It’s advisable to have a return or onward travel ticket, as this may be requested by immigration officials.
Customs Declarations: Be aware of what you can and cannot bring into the UK, particularly regarding food, medications, and other restricted items.
Overall, make sure to keep copies of all your documents, and stay updated on any travel advisories. Safe travels!