Are NCOs allowed to contact a soldier's spouse on their private cell without first contacting the soldier?

Depends on the circumstances and nature of the call. If it was in the interest of the unit and this was the only way to reach anyone, it is legit. If it was personal and didn't have anything to do with military business it's questionable at best. Members are responsible for ensuring their recall information is current and valid. Back in the dark ages when I served (pre-cellphones), brownbaggers would give any old number to fulfill the recall requirement, hoping it would never be called. We would periodically do a recall test to scrub the list. You'd be amazed at what we found out. Numbers might be non-working, the grocery pay phone down the street, a neighbor's phone, you name it. Members either provided a working number or were ordered back into the barracks until they did. 24/7 means just that, and leaders have enough on their plate when the balloon goes up without playing phone tag as a result of irresponsibility of the members.

PFC (Join to see) "Are NCOs allowed to contact a soldier's spouse on their private cell without first contacting the soldier?"

NCO's are charged with doing what ever is needed to accomplish the mission. (Legally, morally, Ethically)

A: Likely is was a switched up number is all. A mistake if you will. ..Someone looked up the number for your husband on a roster and pulled from column A, vice C and the caller got Spouses contact number by mistake...more likely as it looks like you are a SM yourself.."Hey give me Privet Lee's number" and they give that NCO PVT Lee vs PV2 Lee or something.

B: Would you prefer your husband got in trouble for missing an assigned duty vice his NCO calling your phone? Id bet not...so look at it that way and then ask your Spouse to check contact phone numbers when he goes to work next time.

C: When I hear spouses complaining about being called, I almost ALWAYS find out its because the SM has been ditching calls to their phone
Or provided the wrong number or a number that was theirs but later changed when they got a second phone(new phone) and never updated contact info
Or had it happen before and DID NOT personally take the time to make sure the wrong number was addressed and corrected so it would not happen again.

Commonly it is one of those things..
D: If your trying to imply this is an inappropriate contact IOW sexual harassment kind of thing.. STOP writing posts in an Internet forum and get with your spouse and the chain of command NOW.. Im not oblivious nor naive and know crap like that can and does happen...if that is is.....There are folks willing to help...just have to ask.