Originally Posted by
guv1976
Although its schedules for the end of March are not up yet, National Express does offer a one-seat ride from Heathrow 2/3 to Cambridge. The trip takes 2:25 to Cambridge City Centre, but makes an earlier stop at a Cambridge park-and-ride facility. Whether the slightly longer travel time is worth the convenience of a one-seat ride is something only you can decide.
I've previously taken National Express from Southampton to LHR (after disembarking from a cruise), and have found them to be reliable.
Having taken the bus maybe three times to Oxford 10 year ago, that was my first choice. However, my friend at Cambridge thought traffic would be an issue on a Wednesday when I would get out of the airport.
I will look at this again, as I got on well with the previous buses to Oxford.