Purchase a ticket. The cost is $125 one-way or $150 round-trip and includes hydrofoil fare, port dues and insurance in the event of personal injury or loss of luggage. Go to Mahart Hydrofoil's website to order online or call to order over the phone. If you order online, click on "Budapest - Vienna by hydrofoil" on the top left menu navigation on the home page of Mahart's website. From the drop-down menu that appears, click "Booking (webshop)."
Select one-way or round-trip passage from the screen that appears. Enter your personal, contact and payment information. Click "Confirm payment." A receipt will be sent to you confirming your purchase. Retain this for admittance to the hydrofoil. You may also contact Mahart to make reservations by phone.
Arrive early at International Landing Stage H-1056 in Budapest, at least one hour before departure. Bring a valid passport and no more than two pieces of luggage with you. There are a limited number of spots to store bicycles aboard. Allocate about five and a half hours for the journey each way between Budapest and Vienna.