Worldwide assets / worldwide income
There is a basic obligation to declare worldwide assets and income earned worldwide, because at least to determine the respective tax rate, these factors are also required in Switzerland.
In practice, it can always be found that e.g. houses and condominiums located abroad are not specified in the Swiss tax return. In most cases, this is probably due to ignorance of the corresponding declaration obligation or due to incorrect information.
The same applies to foreign custody accounts and the interest and dividends earned from them. In such cases, depending on the double taxation agreement, the taxation right (if DBA is in place) often lies with the country of residence, which is often Switzerland for taxpayers with unlimited taxation in Switzerland. This is despite the fact that in many cases foreign withholding taxes have already been withheld before the dividends are paid in the foreign country.
In order to avoid double taxation, the crediting procedures in the country of residence and the reimbursement procedures in the foreign countries (source countries) must be observed.
Real estate: maintenance of residential property
The maintenance costs for condominiums or single-family houses quickly exceed the flat-rate deduction. Many tax-deductible costs are not always familiar to even investment officers. For example, the fees for water meters, the costs for heating service subscriptions or the effort involved in preparing heating bills. The authority then often deletes the entire deduction and only allows the flat-rate deduction. You can appeal against this.
You can find the deductible maintenance costs for properties in the Canton of Zurich at: To the Cantonal Tax Office in Zurich
Reduction in rental value for underuse
When the children have moved out, space becomes free. Even after the death of a partner or after a divorce. The rental value can now be reduced proportionally by the unused room, a room with more than 30 square meters is even considered to be two rooms. Side rooms, bathroom and kitchen are considered two rooms in single-family houses and one room in condominiums. However, such free spaces may no longer be used.