Have tried looking on this forum but couldn't find the answer.

I moved back to Switzerland from Germany on 1 March. When I crossed the border on this date I included my German car as part of my personal possessions when doing all the paperwork at the border crossing.

I had owned the car for more than 6 months in Germany so didn't have to pay any import tax.

Due to lockdown we didn't manage to get our German plates changed over to Swiss ones until June.

With a new member of the family I now need to buy a bigger car.

I have heard that if I sell the car within 1 year of importing I would have to pay an import tax (around 7% of original value I believe).

My question - should I base this on one year from crossing the border or one year from getting our Swiss plates?

Which govt authority should I ask this question to?

I had no problem "exporting" my car out of Switzerland after 10 months after I brought (impoerted) it with me.
I just returned my 13.20 document at Au customs office and asked if I have to do anything else, they said no so I drove my car out of Switzerland.
And that was it.

You have 12 months to change your plates to Swiss ones, meanwhile you can drive it normally just keep your importing doc with you.

Now, if you don't change your plates to Swiss one after 12 months you should get notified by authorized institution in your canton that you should do it explaining where and what to do.
How do I know this, well funny part, after 14 months (6 months after exporting the car) I got a letter from SCAN (Service cantonal des automobiles
et de la navigation - Neuchatel ) I should register my car to get Swiss plates and scheduling me technical control (Expertise/ Mfk) if I still have the car or if I don't that I wrote a date when I have exported it. After a few emails they told me that the customs office didn't notify them about exportation.

One year of crossing the border.

Tom

1 Year from you entering Switzerland.

How do you know? Is there a govt website with information?