Background
#A PV tax deduction in Thurgau is generally possible for a photovoltaic system on an existing building: the Thurgau tax authority classifies these costs as energy-saving and environmental-protection measures.
Incentives reduce the costs borne by the owner. For a new build or a system installed within five years after completion, the costs are generally non-deductible capital costs. Feed-in remuneration is taxable income from electricity generation; for self-consumption systems, only the excess over grid-electricity costs in the relevant billing period is taxed. This page provides orientation and does not replace an assessment of an individual case.
For your roof
What the deduction means for your home
The report for your address combines the one-off payment, cantonal incentives and tax deduction, with net investment and payback.
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Rather talk directly? +41 78 615 90 58
What drives the economics
#The building history is the first decision: under section 34(1)(1) StG and Thurgau tax practice, PV costs on existing buildings are generally deductible energy-saving and environmental-protection measures. A new build or a system installed within five years after completion generally does not receive this classification.
The five-year boundary is not a planning detail: Thurgau tax practice generally treats investments made up to five years after completion of a new build as close in time to its construction. These costs are capital costs and are not deductible from income as an energy-saving measure, even if the PV system is technically installed later.
Incentives must reduce the cost base: contributions from the Confederation, canton, municipality or a foundation reduce the PV costs borne by the owner. If an incentive is paid only in the following year, the tax practice allows it to reduce the costs in the period in which the costs arose; otherwise, it must be declared as taxable income in the year of payment.
Timing follows the due-date principle: for a PV system on an existing building, costs may not be spread linearly according to depreciation or freely split over two years. If costs cannot be fully taken into account in the tax period, the tax practice allows a carry-forward to a maximum of two following tax periods; genuine project phasing with costs in multiple assessment periods remains possible.
Feed-in and self-consumption must be read separately: under section 23 StG, income from electricity generation is taxable. Under Thurgau practice, a self-consumption system taxes only the amount by which remuneration for electricity supplied exceeds the cost of grid electricity in the relevant billing period.
The roof and asset classification change the result: for a system on a third-party roof, the remuneration is taxable income from immovable property for the owner; the operator cannot deduct construction costs as their own energy-saving measure. Business assets or self-employment follow the usual rules for profit and business-related expenses, not automatically the private-asset practice.
The process in six steps
#Tick off for your project
Classify the building
record the property’s completion date, ownership and use. Use the five-year boundary to check whether the system is on an existing building or close in time to a new build; the Thurgau tax authority decides the specific classification.
Build the cost base
separate the PV system, installation and other project-related items from expenses that are not energy-related. Deduct promised or paid incentives and document whether an incentive is received in the same tax period or only in the following year.
Assign the due date
allocate each invoice to the tax period in which the expense is due. Do not freely split an invoice across two years; instead, check the tax practice’s carry-forward to a maximum of two following periods if the costs cannot be fully taken into account.
Separate income
collect the grid operator’s statements and distinguish remuneration for electricity fed in from the cost of grid electricity. Apply the section 23 StG net approach to the relevant billing period for a self-consumption system; taxability depends on the excess, not on a blanket CHF threshold.
Check roof and asset status
for a third-party roof, the owner and operator must assess remuneration and the ownership consequences of accession separately. In the case of business property or multiple systems, involve the Thurgau tax authority early because business and self-employment rules apply.
Prepare the filing
keep the invoice, due date, incentive decision, grid operator statement and property allocation together. Do not transfer a blanket statement from another canton; for a new build, third-party roof or business asset, clarify the specific classification with the competent Thurgau authority before filing.
Checked for your roof, not just read up on
What the deduction means for your home
The report for your address combines the one-off payment, cantonal incentives and tax deduction, with net investment and payback.
Free and non-binding · no unsolicited calls
Rather talk directly? +41 78 615 90 58
Frequently asked questions
#Sources
#The responsible authorities are decisive. Always verify binding details – amounts, deadlines and conditions – for your specific property against the current status of the respective authority.