Ralls has established himself as a key member of the Cardiff side under Russell Slade, earning a regular place in the Bluebirds starting XI.
Ralls began his career at Aldershot, but it was while playing for Farnborough under-16s that he was spotted by Cardiff scouts
Ralls enjoyed a successful spell out on loan at Yeovil Town in the 2013/14 season, making 37 appearances during his time at the club.
After making 31 appearances in all competitions last season, Ralls has really come to the fore this term with a number of outstanding performances.
Ralls has scored three goals in 16 appearances and his form has not gone unnoticed by the club's hierarchy.
The all-action midfielder still has four years to run on his current deal, but the club are keen to reward him for his progress with fresh terms.