If the probability that you will be randomly selected for SSSS on any single trip is p (which is a number between 0 and 1, say 1 in a 1000, ie 0.001) then the probability that you can make n trips without getting an SSSS is (1-p)^n. So if you fly once (n=1) the odds of not getting SSSS is 999 in 1000. If you 100 times, then your odds are down to ~904 in a 1000. If you fly 1000 times, it is 368 in a 1000... If you fly 10,000 times your odds are 5 in a 100,000,000!

I think SSSS can also be applied to folks who travel with little luggage (ie: no checked bags, just carry on) when traveling transborder/international.

I used a nexus machine (i.e. did US preclearance or arrived in Canada from the US/ overseas) 5 times in a period of about 9 days at the beginning of October, all without checked luggage. On the 5th time, SSSS showed up on my boarding pass.

That time was a HKG-YVR-YUL-LGA trip where YUL-LGA was more than 24 hours later than my HKG checkin, so I couldn't get the boarding pass. Then in YVR I tried to get them to print it in the MLL (since it was within 24 hours at that point,) but they said I couldn't get it until I got to YUL since "YVR couldn't print the boarding pass for a flight leaving YUL the next morning" :confused::confused: Anyways, I talked to a concierge, and after 10 mins of fumbling with my file, out came a YUL-LGA SSSS boarding pass. I don't know if all that fumbling around was what caused the SSSS to show up, or vice versa and the SSSS designation was what made it so difficult to get the boarding pass...

I would guess its the latter. Did they really drill you even though you had Nexus or was it a quick in and out?

What does using Nexus have to do with SSSS on BP? :confused:

Here is a few older but relevant threads:

Air Canada Security

SSSSed?

I had it four times in the last 12-18 months, twice from LAS home to Canada, once to LAS and once from HNL. On the third time, I asked why...Homeland Security (and AC) told me that were said several factors, a. random (I'm assuming the HNL flight), b. last minute ticket (which the three LAS ones were), and c. cash ticket (which didn't apply).
But, I've flown to/from USA a few times since, and haven't had it again.

Had it a couple times flying regional in the US with UA. Never on AC.

Had SSSS on SFO - YVR in 2006 on AC on my sister's AC staff standby passes.

I met all the criteria:

Solo - was traveling with my sister but she was on a separate reservation
Male
One way ticket
Short notice

Nothing since.

Once only, one way flight RSW to YYZ, few years ago, might not even have been AC; can't remember.

They didn't really do anything all that thorough back then, just asked a few extra questions about how I got there and why I needed a one way ticket.

Got SSSS once and chose to have a hand swab!! Have been selected "at random" a few times--the last one was when I was not carrying any hand baggage--my stuff was in Mrs.ac777's purse!!

I was given one in August.

Male
Solo
Two separate one way tickets.
YYC-DCA......SSSS
ATL-YYC nothing.

It was no big deal here, I was just put through the body scanner. I was ready for it!

I've had it once, and it was odd scenario. Was in TUS waiting at gate to fly TUS-PHX-YEG on US. TUS-PHX cancelled due to Mechanical. Rebooked by US at gate to fly on immediately departing DL TUS-SLC-YEG flight. Reprinted boarding pass had SSSS. No one noticed, but was then denied boarding until I went back out and re-screened with SSSS. Held the plane for me while I did this.

That happened to me at YQR too. They screened me right at the gate (they held up our flight for about three or four minutes for them to do it). It was easy - we chatted while the CATSA people checked out my bag and off I went.

Ask for the CATSA stamp if they forget at security!