If you will be driving on the Austrian motorway (Autobahn), then you will need a valid ‘Vignette‘ sticker on your windshield. Otherwise you will receive a fine (there are camera spot checks).
You can buy the Vignette at petrol stations, ÖAMTC, post office, Tabaks (newsagents) or ASFINAG toll stations. You can also buy a digital version on-line – advantages are that it’s connected to your license plate so if you change cars, replace your windshield etc you don’t need to buy a new one. Plus it can be set to automatically renew so you don’t need to worry about remembering each year. The only downside is you have to wait 18 days before you can use it when buying on-line (due to the 14 days consumer rights regulation for on-line purchases). But you can also buy a digital one at the physical places mentioned above, and it will be activated immediately.
If you live in Austria, you will most likely want to buy the one year sticker (there are also shorter options – 2 months and 10 days). Each year there is a grace period until January 31st to buy the current year’s sticker, (assuming you already have a sticker from the previous year).
The ASFINAG have a good English webpage with useful info on how to purchase and other FAQs.
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