How to go from Negombo to Anuradhapura without backtracking through Colombo

You absolutely do NOT need to backtrack to Colombo. Three good options Negombo to Anuradhapura: (1) Direct bus on the Puttalam route: there are buses from Negombo bus stand running up the west coast to Puttalam and onward to Anuradhapura (~5 hours, very cheap). (2) Private driver: a one-way transfer Negombo to Anuradhapura is around 18,000 to 22,000 LKR, takes 4 hours, comfortable and lets you stop in Wilpattu for a half-day safari if you leave early. (3) Train: take a short train Negombo to Kurunegala, change to the Northern line up to Anuradhapura; slower but scenic and inexpensive. Most travelers go with option (2) and turn it into a Wilpattu safari day plus arrival at Anuradhapura by evening, which is a great use of the day.