Since the distance between Kolkata and Jammu is around 2000km, it is not advisable to travel there by car or bus which takes around 30 hours approx. You can travel to Jammu by flight which takes arou (Read More)nd 6 hours. The journey by train is 36 hours long but is quite comfortable.
So if it suits your budget the best way to travel from Kolkata to Jammu is by flight.