I've been in an exclusive relationship right now for closing in on a year, but I more or less pretty much explicitly stated it in my profile and unless you're afraid of being doxxed/outted I kinda recommend you all do TBH. The "less" part comes in the sense that I firmly believe with dating profiles you kind of want to express a personality/flavor and be fun rather then just listing things out. IE rather then just flatly stating:

"I am a communist and would ideally like to date fellow comrades" I did a contra points reference in my profile and had the line:

"I hate when people call me a champagne socialist. I've never even been to the champagne regions of France and am therefore obviously a sparkling marxist." Had a pretty good reception.