Hi Brigi
For technical reasons, it is not yet possible to purchase a ZVV extention ticket only with certain zones on SBB.ch. It is imperative to enter a start and end destination station. Although the stretch of journey is shown shortly before finalising the purchase, this is not indicated on the ticket. Only the amount of additional zones are correctly shown.
We therefore recommend that you enter a stop within the zone, which is the closest to the area of validity of your already purchased ticket, as your starting point.
For example:
You already possess a ticket for the zone 110 and would like to travel to Winterthur. Enter a place in the neighbouring zone 121 as your starting point ( e.g. Wallisellen) and “Winterthur” as your end destination.
Kind regards
SandraI