Stephen Colbert's Final ‘Late Show’ Episode Date Announced

Stephen Colbert has finally locked in the end of "The Late Show" ... with the curtain set to fall for good on May 21, closing out a CBS late-night run that’s lasted more than 30 years.

Stephen broke the news during a taping of "Late Night With Seth Meyers" on Monday ... officially putting a date on the farewell that’s been looming since last summer.

Remember, CBS and parent company Paramount Global announced plans to cancel the show back in July, blaming straight-up financial reasons.

But the move raised eyebrows, as it followed Colbert publicly slamming Paramount for settling Donald Trump’s "60 Minutes" lawsuit ... calling it a "big fat bribe" from the company.

But, his TV monologues might not be done for good -- 'cause he’s already joked about wanting a job at TMZ ... and yeah, we’ve got the receipts!