I am a local from Vienna and can elaborate: On Vienna Hauptbahnhof (HBF/Main Station) there are basically 2 diffferent locker spaces. One on the main entrance floor / floor zero (German: Null) and one on floor minus one (German: Minus Eins). Floor zero is operated by the Austrian train company (ÖBB), reviews are mixed especially with cleanlyness. These lockers should still accept cash money (coins only). The lockers on floor minus one are operated by a company called Tamburi (Web: https://storage.tamburi.com/en ). They have bigger lockers, they only accept cards and no cash. I personally would NOT use the lockers from this company. Very high rate of technical problems, I personally lost a piece of luggage with them (or rather: they lost it - not me), check their ratings on TrustPilot -> horrible rating, horrible stories (as a local Austrian guy I'm ashamed a company like this can even operate legally here): trustpilot.com/review/tamburi.at, most of the upcoming ratings are in German - use Google Translate for those; at.trustpilot.com/review/tamburi.at, similar horror stories on their facebook page and instagram, here you have an article from a customer protection service site (you have to use German to English translation here again) Tamburi Locker: no access possible. But through a service called "Bounce" there is a good alternative for these locker boxes/spaces, arount the main station are enough local shops which also offer locking your luggage. There you have real people as 'security' (no error-prone automatisation) and usually they have access to their video surveillance - on main station you won't have access to video surveilance; only if you go to the police and their recordings are deleted after 120 hours (5 days) plus you have to trust them on what tehy tell you - they wont show you actual footage and in general it is a process taking longer then just one day usually. There is a search engine where you can find those Bouce shops and other locker boxes araound main station: bounce.com/luggage-storage/vienna. These are just regular shops whith regular opening hours (you need to know tha for pick-up) but they are capable of protecting your stuff better then those crappy lockers on main station where you don't have real persons for service, only a service hotline and remote management (wich will nocht work all the time). So I personally would use Bounce or ask the hotel where you stay (usually they can take care of that also). I hope this helps - for any further questions feel free to ask (a I could even go to main station anytime to look things up or see if something 'new' is happening there).