Heaton, who turns 18 before pre-season, has penned a one-year deal to secure his place in Phil Parkinson's first team squad for the forthcoming 2014/2015 season.
The left-footed centre back joins Oliver McBurnie in moving up from City's title-winning youth team of last season into Parkinson's senior set-up.
Heaton said: "It is ever boy's dream (to sign a professional contract) and it is going to be a big year for me now.
"I have to prove myself to the gaffer and show him what I can do.
"I have signed my deal but the hard work starts now really. I have to show the gaffer what I can do and hopefully prove to him that I can play in a first-team environment.
"Last season was really enjoyable with the youth team but that was all in preparation for turning pro and getting myself ready for this year. I'm really looking forward to the season ahead now."
Although he never made a first team appearance last season, Heaton did travel with the squad for a couple of City's League 1 away fixtures.
Heaton, who had previously been part of City's Academy/Centre of Excellence programme, originally left Valley Parade as a 14 year-old to join up with Premiership giants Liverpool.
During his time on Merseyside, Heaton also represented England at schoolboy level.
The towering defender re-joined City in May 2013 to finish the second year of apprenticeship with the club's youth team. The deal to bring Heaton back to Bradford from Liverpool included the option of a one-year professional deal in it.
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