The two players - who turned 17 last week - have been with Palace since Under-11 and Under-9 levels respectively, each earning international minutes this year for England Under-17s. Mooney is also eligible to play for the Republic of Ireland and Raymond has featured for Wales.
Speaking with Palace TV after putting pen to paper, Mooney said: "It is a proud moment for me, my family and everyone that has helped get me to where I want to be today - the smile on their faces is just awesome and I'm looking forward to the future."
Raymond echoed his teammate’s comments, adding: "I grew up in South Norwood, so I've always seen the stadium from my bedroom window and heard the crowd chant.
"Back when Palace were in the Championship, when I was eight or nine. I saw Zaha, you know, just doing his thing and it is a great feeling to know that I am part of that now."
Upon the exciting news for the pair, Chairman Steve Parish added: "I’d like to congratulate Fionn and Jadan on becoming contracted, professional footballers. This is an important moment for them and their families as they reflect on their respective journeys through our Academy so far, and one they should celebrate.
"But now is the time for them to refocus, work even harder, and continue to put in outstanding performances for our Academy teams. I wish them every success for the future here at Crystal Palace.”
Find out all there is to know about our two exciting talents by hearing what they had to say in their interview with Palace TV below.
Follow how Mooney and Raymond's Under-18 side get on this season by adding their fixtures to your calendar.