They understand that this might come quite unexpected (no kidding ) but they happily provided me with a payment slip to pay them the missing taxes.
After original shock - and to be honest - fit of rage, I sat down to look into this matter.
So what actually happened is that in all the months where I got irregular salary (means Mays when I received bonus and Novembers when I received the 13th salary) I have been charged the same tax percentage as in the other "regular" months, i.e. I received higher salary, but did not get charged higher tax.
As a side note - a tip for you out there paying tax at source - do not quit your job November being your last working month. I though it was an excellent idea - stop working in November, have December, i.e. Christmas time, off and be covered by the 13th salary, etc. until I find a new job. Well yeah, it seemed a great idea then, but now I realise how stupid it was. Because I did get my 13th salary and unused holidays and overtimes paid out in November, i.e. I had a triple salary to cover me for a while. But triple salary also means that my taxes got higher. And not just three times, but almost EIGHT times higher!!! *facepalm*
And I do understand that if I earn more I have to pay more taxes, I do not have problem with that. But I wonder - how on earth can something like this happen in the first place? I worked there 2014-2016 and after 2 years they come to me like - hey, btw...
Did anyone else have to go through something similar?
I also did some research and found the following info on the ZH taxation office website:
If the employer charged an incorrect tax at source, this can be claimed additionally by the cantonal taxation office within 5 years from the end of the calendar year, in which the taxation took place. Separate procedure applies for claims outside the 5 year period.
https://bit.ly/2uyhCbE (german)
So, yeah, they can claim the tax from me retrospectively (no surprise there), but do you think I have the right to at least request an instalment plan? Because it's not an insignificant amount for me, so I would appreciate if I could pay it back in several payments. As it was their mistake, which left me in this messy situation, in the first place, they should agree to that? Don`t you think?
Will be glad to hear any feedback or advice on how do you think it would be best to proceed.