Long Island Rail Road operates a train from Riverhead to Montauk 5 times a day. Tickets cost $9 - $14 and the journey takes 1 h 3 min. Alternatively, Hampton Jitney Inc. operates a bus from Riverhead to Montauk once daily. Tickets cost $21 - $25 and the journey takes 1 h 30 min.
How to get from Riverhead to Montauk
From Riverhead taxi to Westhampton then train to Montauk. 1 h 13 min $42. From Riverhead taxi to Manorville then bus to Montauk. 1 h 41 min $62. From Riverhead taxi to Montauk. 57 min $183. From Riverhead drive to Montauk. 57 min $5.