Application before or after installation? It depends

There is a sentence that appears in almost every guide on heating public subsidies: Apply first, then commission. It is well-intentioned, but as a general rule, it is wrong — and that can be expensive, in both directions.

Three systems that contradict each other

The federal public subsidy „Kesseltausch“ (boiler replacement) works with a registration. It reserves the money; from then on, you have nine months for installation and final billing. You can also register for a system that has already been installed (services from 3 October 2025 are eligible for subsidies) — the risk lies elsewhere: if the budget is exhausted, the agency will no longer accept registrations, no matter how far along you are. Before registration, an energy consultation (Energieberatung) of the federal state is mandatory.

Some public subsidies require the application before delivery, such as „Sauber Heizen für Alle“ (Clean Heating for All) or, in Styria, the replacement of an old heat pump or biomass heating system. Vienna advises only commissioning after approval; retrospectively, it is only possible there with invoices that are at most six months old.

Many federal state public subsidies work the other way around: they require the completed system and ask for the invoice and often the commissioning protocol (Inbetriebnahmeprotokoll). An application "in advance" is not even provided for there.

What it looks like in practice

Vorarlberg is a clear case of "afterwards": the complete public subsidy application must be submitted no later than six months after commissioning, and in 2026 in any case by 31 December. Read more about this in the article on the deadline at the end of the year.

Carinthia has two paths. New cases run via the heating replacement (Heizungstausch) according to Section B: online application after completion of the work, with confirmation from the company, without a federal public subsidy as a prerequisite. Only those who were registered with the federal government by 10 July 2026 use Section E — and that requires the payout letter (Auszahlungsschreiben) from Kommunalkredit.

Other federal states require the application after implementation or allow both. Which rule applies to you and in which order is shown to you by the Förder-Manager (public subsidy manager) with your details — including deadlines and forms. The public subsidy office (Förderstelle) is always binding.

The mistake that really costs money

It rarely happens out of negligence, but rather under time pressure: the heating system fails in winter, the company has an appointment available at short notice, and the installation happens before anyone has thought about paperwork.

For public subsidies with an "application before delivery", the money is gone. With the federal public subsidy, it is not automatically lost — but anyone who registers late risks the budget being exhausted by then. In 2026, this happened on 10 July.

The reverse mistake also exists: anyone in an "afterwards" federal state who waits for months for an application confirmation that is not even provided for there may miss the submission deadline.

How to proceed safely

Before placing the order, clarify which pots are eligible. Federal government, federal state, possibly municipality — and for each separately: before or after?
Do everything that is required "before delivery" first. For the federal government: energy consultation (Energieberatung) and registration early, while budget is still available.
Note down deadlines as soon as the system is running. Six months after commissioning sounds like a lot, but in everyday life, it passes quickly.
Collect all documents, even the seemingly minor ones: invoices, commissioning protocol (Inbetriebnahmeprotokoll), device data sheet, proof of disposal (Entsorgungsnachweis), and, in the case of federal participation, the payout letter (Auszahlungsschreiben).
Ask the installer who submits what. Many take care of the process — but not all, and rarely everything. This should be clarified before placing the order.

A note on the current situation

Federal funds for 2026 have been exhausted since 10 July; a budget has been announced again for 2027, but the conditions have not yet been published. Most federal state public subsidies continue to run independently of this — check your federal state before you count on money that is currently not available.