Blagoevgrad–Rila buses operate hourly, the last returning to Blagoevgrad around 8pm (2 lv, 45 minutes). Two daily buses also serve Sofia (9 lv, two hours). If connecting from elsewhere, use Dupnitsa–Rila buses (three daily).
Three daily buses (2 lv) connect Rila village to Rila Monastery. If you're making a day trip from somewhere other than Rila village, start early to leave enough time for connections.