Rent is not tax deductible. Interest is.

If you own a property, there is an assumed rental income (Eigenmietwert, or Own Rental Value) which becomes taxable, which can be offset by mortgage interest ... interest on all debts always being tax deductible.

I have no idea what PK Winterthur is, ask your HR dept. It may be "Pensionskasse" which is Pension Fund, and the company might be Winterthur Insurance; which recently changed its name to Axa-Winterthur.

Hope this helps,

Lisa