Anyone know how long they were put together in the states? My stainless 232 has the German frame and DE marked barrel but NH slide. Just trying to figure out when it might have been produced.

To my knowledge, all P232 pistols were assembled in Germany. My late production example (S 3313xx) also displays SIG Sauer's New Hampshire address as well as the DE country of origin code. The US address simply identifies the importer, not the point of assembly.

I guess I thought this was the case since they took "made in Germany" off of the slide. Mine is S3167xx. Also can't find the typical two digit production code. I could certainly be wrong. Wouldn't be the first time!

Does your gun have vertical slide serrations instead of the older slanted style? If so I believe most if not all of those would be NH made. Or at least NH assembled.

A sure way to tell would be if your gun lacks any german style proofmarks, date codes and serial number.

Not sure exactly when they started doing that but I recall having seen these new style slides going back at least several (5?) years.

My pistol displayed vertical slide serrations as well the German "DE" country of origin identifier. It was manufactured in early 2014 with importation ceasing in July of the same year.

Yep, vertical and no proof marks. Only DE is on the barrel. And "made in Germany" on the frame, like one of my 226 models assembled in NH.