It may be that you've already done this transfer and discovered the answer yourself (!), but it is a UK Government requirement that all departing passengers are security screened to UK standards. This includes arrivals from the EU and the UK's Common Travel Area partner, the Republic of Ireland. The only transit passengers who do not have to pass through secondary security are those who have originated from a UK regional airport (plus Belfast in Northern Ireland, which falls under the UK standards), so OSS will not be implemented in the UK - probably ever.

That's unfortunate. I ended up changing my travel plans to transit through ZRH instead, which was a breeze compared to Heathrow! No OSS though.

Big changes in the transborder (going to US) at YYZ. In the past it was go through customs then go through security, now they've flipped it. So I assume ppl flying through YYZ onward to the US will bypass security very soon.

Yup, already in this thread

http://www.flyertalk.com/forum/air-c...ocess-yyz.html

The path will occur well before that, likely up in the arrivals hallways. The key here is that OSS is negated the instant a person has access to any checked bags (not just their own) or non-OSS screened passengers. So they need to capture and process OSS screened people as early in the stream as possible to prevent contamination.

What does OSS - Zone 1 mean?
 

So on my boarding pass today, under boarding zone it lists "OSS - Zone 1". I've certainly never noticed the OSS notation before. Anyone have any idea what it means? The gate agent had no idea, and now I am curious.🤔

One Stop Security

Countries that participate in OSS don't require OSS PAX to be security screened at onward airports as they recognize the original OSS countries security standards.

Just flew SJC-YVR-YYC yesterday and can confirm that OSS on my boarding pass made absolutely no difference at all to security screening. I still exited the transborder area and had to go through the main YVR security screening process. I had Nexus, so that sped it up. I actually did not know what OSS meant until I came to Flyertalk later, but no Air Canada agent seemed to know what it meant either.

Thanks Dorian. Ironically, it made no difference to the security screening in YVR; I still had to exit the secure area and clear security once again in YVR.

I guess the CBSA doesn't recognize their own security as secure enough.

I think the OSS initiative may be why we saw the revamp of transboarder processes at YYZ - for connecting pax, no need to be rescreened post-customs.

I hope that's the case eventually, but I went US -> Canada last week with "OSS" on my BP and still needed to go through the regular domestic security screening.

That's not possible, because you have to take your shoes off to fly to the US.

It may eventually affect the other direction though.

None of Canada's airports are set up for this yet, I had to go through security again at both YYZ & YVR in the past 30 & 60 days. It's a great concept and sure looks nice on your BP and yes your bags do go to your final destination in Canada without having to pick them up when you land in Canada, but you still need to enjoy the security ritual after clearing customs.