Mitchell follows teammates Marc Guéhi and Conor Gallagher in earning a Three Lions nod for games with Switzerland and Ivory Coast. It is also Guéhi's first call-up at senior level.
Mitchell has not yet represented England in any capacity, but earned his selection during a phenomenal personal season in which he's played 33 games, receiving Palace's Player of the Month in November.
Before the call-up, Southgate said of Mitchell: "Tyrick, we’ve been really impressed with... I think he’s been very good with his defending. He gets out quickly to people and in the biggest games against top opponents he’s coped really well."
England play Switzerland on Saturday, 26th March at 17:30 GMT and Wilfried Zaha's Ivory Coast on Tuesday 29th at 19:45.
Mitchell becomes the eighth first-team Palace player to face international duty this month. You can find out every Palace call-up and when the lads might be in action here.