Phetprasert Tour operates a bus from Phitsanulok to Chiang Mai every 4 hours. Tickets cost $9 - $11 and the journey takes 5 h 11 min. Alternatively, State Railway of Thailand operates a train from Phitsanulok to Chiang Mai every 4 hours. Tickets cost $12 - $18 and the journey takes 7 h.
From Phitsanulok bus to Chiang Mai. 5 h 11 min ฿337. From Phitsanulok train to Chiang Mai. 7 h ฿482. From Phitsanulok drive to Chiang Mai. 4 h 54 min ฿1200. From Phitsanulok taxi to Phitsanulok airport, fly to Chiang Mai airport, then bus to Chiang Mai. 4 h 9 min ฿3103.