You are required to have a ticket that has been validated on you at all times while on the Vienna Metro. Uniformed and plain clothes ticket inspectors are patrolling at all times and if you are caught without a valid ticket you'll have to pay a €103 penalty fare.
A single ticket costing €2.40 is valid for one journey within a zone. You can change as often as is necessary but you may not travel on a circular route or go back to your starting point.
2) 24/48/72 Hour Passes
You can purchase passes lasting 24, 48, or 72 hours from the time of validation. A 24 hour pass costs €8, a 48 hour pass costs €14.10 while a 72 hour pass costs €17.10.
3) Vienna City Card
These are also available for either 24, 48 or 72 hours and are good for yourself and one child under 15 years old. The Vienna City Card also offers discounts and benefits at some Vienna attractions and restaurants. The card is priced at €13.90, €21.90, and €24.90.