Funding & Bureaucracy · Chapter 25
KfW heating subsidy: the process
The strict sequence from BzA through application and approval to payout — and the one trap many miss.
As of 2026 — subsidy rates and details change (BEG reform of 21 July 2026). Verify figures and steps with KfW or the specialist company before applying.
KfW funds replacing a fossil heating system with a heat pump via a grant (up to ~70% of eligible costs, capped). The order of steps is legally strict — miss it and the funding is gone.
The chain in six steps
- BzA (Bestätigung zum Antrag / confirmation for the application). The specialist company (or an energy-efficiency expert) issues it — only a registered company can. It's the key that unlocks everything.
- Apply in the "Meine KfW" portal — with the BzA, before signing the binding contract.
- Approval / Bewilligungsbescheid from KfW.
- With the approval, to your house bank for the KfW Ergänzungskredit 358/359 (its own chapter).
- Installation → final invoice → you pay.
- BnD (Bestätigung nach Durchführung / confirmation after completion) from the company after payment → with it you draw the grant.
In short: the BzA gets you to approval; the BnD gets you to payout.
The trap: "apply before you order"
The most common expensive mistake: sign the contract first, then apply for funding. That's too late. The solution is a conditional clause: the order confirmation is made explicitly dependent on the funding approval. That preserves the "apply → approve → contract/start" order even though you've formally placed the order. Many specialist firms provide this clause on their own.
What influences the subsidy amount
- An old oil/gas boiler (> 20 years) helps with the speed bonus (replacing old fossil heating).
- Multiple residential units (with official rental contracts) can raise the eligible-cost cap — tell the specialist company early so the BzA reflects it.
- Income bonus: below a household-income threshold there's an additional bonus.
What runs separately
Windows/the building envelope are not funded here but via BAFA (BEG EM) — a different pot that combines with the KfW heating subsidy. PV modules/inverters are generally not subsidised (they get 0% VAT instead).
In short: BzA (only from the specialist firm) → apply at "Meine KfW" before the contract → approval → bank → installation → BnD → payout. The conditional clause saves the sequence. Report a second unit and an old oil boiler early.
Next, the loan part: the KfW Ergänzungskredit 358/359 via your house bank.
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