Do you have to stand at Parade Rest for a Senior NCO when not in uniform?

Well I would say it depends on the time and place. If you are at a bar overseas it may not be a good idea and well if you are getting yelled at in the B's well you probably should. Common sense is good for this one.

You bet your rank you do!

I did. I do now, even as a civilian.

SGT (Join to see) 24/7 Soldier. Here is my personal take: If I am getting corrected or correcting someone, I could care less who is or is not wearing a uniform. Do the right thing, ALL of the time. Its simple.

Your post is pretty short and leaves much to the imagination. I'm reading this as a way to "buck" the system. Don't buck the system like this. If your going to buck the system, do it through outstanding leadership and work ethic and raise the standard in your organization. Don't settle for "meets standard"...exceed it every day. Do your absolute best at every task you are given, it will make a difference.

Bucking the system in a way that can irritate someone, might not play out so favorably for you. Pick and choose your battles.

The thing to remember, it is a respect and tradition oriented culture. Parade rest is situation dependent meaning that it depends. No senior NCO is going to expect you to drop everything you are doing to stand at parade rest if you are playing sports, spending time with your family, etc. On the other hand, if you are about to head off on liberty or pass in civilian attire, a senior NCO like a First Sergeant who's main job is to make sure you are treated with respect, trained well, and that there exists good order and discipline, so if he ask you in their office for some reason...then it is parade rest.

If you are a professional, you should go to parade rest or attention as applicable if you know the individual is a higher rank than you. It is a sign of respect for the office that you and the other hold.

If you deem him or her worthy and know them to be as such then yes.

I never had any experiences that lend credence to my opinion on this subject but I think I would go to parade rest, even if somewhat of a muted form. If we were both in civvies, or they were in uniform and I was in civvies, I would simply stand with my hands behind my back and feet shoulder width apart.
In any case, I would give the senior NCO the choice to tell me that I can forego the 'parade rest' in informal situations. Kind of like what happened to SGT Rojas.
Reminds me of the ol line that my first team leader taught me that applied to salutes. I thought it was appropriate in this case as well.

If in doubt, whip it out.

You are not for the uniform you are doing it because of Honor, Respect and Loyalty.

SGT (Join to see) Here is my question. By your rank I' am guessing you just joined when you went through boot camp did they not give you a book? When i went to boot camp we received the Blue Jackets Manual it cover a wide range of things like customs and traditions. Our RDC (Recruit Division Commanders) Also covered how we address those senior to us once we leave boot camp. My other question is are you trying to find a way to "buck" the system. I have been there when i was a junior troop and if that is the case you are looking to make a long time at that command. I can tell you the reason i only made it to E-5 with 10 years in was because my evals suffered from finding ways to "buck" the system. So show the proper respect the situation dictates you don't have to respect the person in the uniform but you damn sure have to respect the rank. And if your just genuinely seeking guidance because you don't know there is some good advice from Army NCO's here