King Daniel wrote:
No money isn't post-TOS, I'm pretty sure.
The idea first cropped up in Star Trek IV: The Voyage Home. The Original Series made numerous references to money and even had the scene with Uhura haggling with Cyrano Jones to buy a tribble on Space Station K-7. Voyager later retconned the demise of money to the 22nd century in the episode "Fury". Then Kirk offered to pay for Uhura's drink in Star Trek (2009), re-un-retconning it. Sort-of.
Not to mention references to "credits," Kirk telling Scotty he's "earned his pay for the week," and didn't Uhura explicitly state that Mr. Brack bought
his planet? Heck, Sulu even explicitly mentioned pennies in a mathematical example.