Despite being the more dominant side over Reading, the 'Bluebirds' were denied the three points. However the outcome was irrelevant after Birmingham beat Fulham 3-1 on Sunday.
It was a case of double celebration as not only did Cardiff manage to secure their promotion, but Reading also guaranteed their survival in the Championship.
Cardiff manager Neil Warnock took over at the club in October 2016, and has transformed his side from relegation-threatened in the second division to a stunning return to the Premier League next season.
The atmosphere in the stadium was electric, particularly after Reading fans began chanting ''We are staying up'' once they realised that their relegation rivals, Barnsley and Burton, were headed for defeats.
Not long afterwards, Birmingham's opening goal prompted a joyous celebration from Cardiff fans as the prospect of promotion edged closer when news came in of the matches elsewhere.
Once Birmingham secured their lead over Fulham, fans at the Cardiff City Stadium flooded onto the pitch to engage in early celebrations as they guaranteed their top-flight return for the first time since 2014.