1. Which funding programs exist in 2026?
The funding landscape for replacing a heating system in Germany is noticeably tidier since the BEG reform of 2024 than it used to be, but still multi-layered. The most important building blocks for 2026 are the BAFA heating subsidy as a direct grant, the KfW supplementary loan 358 and 359 for residual financing, the broader BEG residential building program for major renovations, and supplementary state and local utility funding pots that may be added depending on where you live.
BAFA heating subsidy: This is the go-to office for the classic heating system replacement to a heat pump. Online application with the Federal Office for Economic Affairs and Export Control (BAFA), grant between 30% and 70% depending on the bonus stack. The BAFA subsidy was structurally separated from the KfW in 2024 and unified. As of May 2026 the conditions are stable.
KfW 458 heating subsidy: Sounds confusing, but it is important to know. KfW 458 is the successor program number for the old BEG-EM subsidy. It is the formal designation of the BAFA heating subsidy within the KfW system. For most households the application office is BAFA, not KfW. Anyone who mixes these up gets rejected for using the wrong application office.
KfW 358 and 359 supplementary loan: A low-interest loan for the portion that the BAFA grant does not cover. Maximum loan amount 120,000 EUR per residential unit, term 4 to 35 years. Prerequisite: BAFA approval must already be in place. For households with gross annual income below 90,000 EUR there is an additional repayment subsidy of 2.5% on the loan amount, which reduces the effective burden further.
BEG residential building (WG): Anyone not only replacing the heating system but planning a comprehensive energy-efficient renovation (insulation, windows, ventilation, heating in one package) can use the BEG-WG program. Application office KfW, higher funding amounts possible, but in return considerably more requirements and mandatory certification of the energy-efficient house class. For a pure heating system replacement, BAFA is the simpler path.
Municipal utility and state programs: Some municipal utilities and individual federal states offer additional heating replacement bonuses. The amounts vary widely, from a symbolic 500 EUR to several thousand euros in individual municipalities. Important: these bonuses are not available everywhere and often change annually. Before applying, check with your local energy provider and your federal state. In this sub-page we focus on the nationwide BAFA-KfW funding, because it applies equally to all households.
A note on clarity: the stacking possibilities between BAFA, KfW and municipal pots are usually not arbitrary. The BAFA grant and the KfW supplementary loan can be combined, municipal pots can often be added on top, but the BEG-WG comprehensive program usually excludes a parallel BAFA heating subsidy. If you are unsure, consult an energy efficiency expert in advance who can check the program combinatorics for your concrete situation. More on the heating oil price dynamics, which make a heating system replacement economically attractive, can be found in our glossary.
2. The funding stack: 30% + 5 bonus components
The core of the BAFA heating subsidy 2026 is the 30% base grant, which every applicant receives for a classic heating system replacement to a heat pump. On top of this, up to five bonus components can apply depending on the situation. In total, funding is capped at 70% of eligible costs, with a maximum assessment basis of 30,000 EUR. This yields an absolute maximum funding amount of 21,000 EUR per residential unit.
Standard subsidy for replacing a heating system with a heat pump. Applies to all applicants without additional conditions.
For replacing an old oil, coal, night-storage, gas storey or functional gas heating system older than 20 years.
For households with taxable annual income up to 40,000 EUR, owner-occupied apartment or single-family home.
For applications submitted by 31 December 2028. Decreases gradually after that. As of May 2026 still available at full level.
Particularly efficient heat pumps with high annual performance factor (SCOP from 4.5 for air-to-water).
The bonus logic is cumulative, but most applicants do not qualify for all bonuses at the same time. The climate bonus requires an old existing heating system (typically oil or gas, minimum 20 years old for gas). The income bonus only applies to low household incomes and exclusively for owner-occupied residential property. The speed bonus is time-limited. The efficiency bonus requires higher technical performance and is not achievable for all heat pump models.
Important: the 30,000 EUR assessment basis includes not only the heat pump itself but also the associated installation costs, hydraulic balancing, storage, buffer storage, radiator adjustments and dismantling of the old system. Anyone planning a complete renovation can quickly max out this assessment basis.
A realistic example to put things in perspective: an average air-to-water heat pump for a single-family home costs around 25,000 EUR to 32,000 EUR including installation (as of spring 2026, depending on system size and regional installer prices). With a 28,000 EUR assessment basis and 70% funding, the owner receives around 19,600 EUR as a grant, and the own contribution drops to about 8,400 EUR. This makes the heating system replacement economically more attractive in many cases than a gas condensing boiler replacement, which is not funded.
If you also want to know how the pass-through effect with rising Brent prices affects your ongoing heating oil costs and makes the replacement pay off even faster, take a look at the methodology overview. The combination of subsidy and avoided extra costs is the real argument for the heat pump in 2026.
How much will the next Brent shock cost you without a heat pump?
While you plan the swap, the next oil price jump could blow up your heating oil bill. Work out in 60 seconds what the shock concretely means, and compare it with the funding savings.
Calculate in 60 seconds3. Who gets what? 3 persona examples
To make the funding stack tangible, here are three realistic examples for different households. Each persona is based on 28,000 EUR investment costs for an average air-to-water heat pump including installation. The numbers show how the stack comes together depending on the life situation.
Persona 1: The Meier family
The Meiers have lived in the row house for 12 years, the old oil heating is still running, but the last heating oil bills have been tough. A new oil boiler has not been eligible for funding in new builds since 2024 and is only restrictedly permitted in existing buildings. The family decides on an air-to-water heat pump.
With a 28,000 EUR assessment basis and 70%, the Meiers reach the maximum funding rate. Own contribution stays at 8,400 EUR. The 21,000 EUR cap is not maxed out because the investment costs are below 30,000 EUR.
Persona 2: The retired Bauer couple
The Bauers have lived in their own home for 30 years, the heating system has accompanied them through every crisis. With their low retirement income, a new purchase would normally not be affordable. The income bonus is what makes the decisive difference here.
With all bonuses, the Bauers would arithmetically reach 100%, but the cap pulls funding back to 70%. Still the full funding amount, own contribution 8,400 EUR. With the KfW 358 repayment subsidy of 2.5% on a supplementary loan, the effective burden is reduced further. Realistically manageable for a retired household.
Persona 3: Single Schmidt
Schmidt bought the apartment in 2018, the gas storey heating is not yet 20 years old but runs uneconomically. The climate bonus has a hurdle: the gas heating must be older than 20 years, otherwise no climate bonus. With model year 2005, the threshold was reached in 2025, so as of May 2026 just barely.
By choosing a highly efficient heat pump, Schmidt reaches the efficiency bonus, which arithmetically would amount to 75%. The cap pulls it down to 70%. Own contribution 8,400 EUR. Compared to a gas condensing boiler replacement, which is not eligible for funding and costs about 12,000 EUR, the funded heat pump is economically more attractive, because the running costs are 30 to 60% below the gas heating.
The three personas show the spectrum: the Meier family without the income bonus lands at 70% via the old oil heating plus speed bonus. Retiree Bauer has all three main bonuses, but the cap limits at 70%. Single Schmidt just makes it to 70% via the efficiency bonus. In practice, this means: anyone submitting an application in early 2026 almost always reaches the maximum funding rate, as long as at least the climate bonus applies. This is the most important message for everyone planning a heating system replacement but hesitating: the 70% are not rare, they are the normal case for existing buildings with old oil or gas heating.
4. Application path: 4-step walkthrough
The application at BAFA runs online and follows a clear sequence. Anyone who sticks to the order gets the funding approval in around 4 to 8 weeks. Anyone who does not stick to the order gets rejected. The most common reasons for rejection are listed in the next section, here first the clean path.
- Step 1: Commission an energy efficiency expert The first step is to find a qualified energy efficiency expert. The official expert list of the dena (German Energy Agency) is the mandatory starting point. Search on dena.de for listed experts in your region. The expert prepares the confirmation for the application (BzA, Bestätigung zum Antrag), which you need to even submit the BAFA application. The BzA is a technical document that confirms the funding eligibility of the planned system, including annual performance factor, hydraulic balancing and minimum efficiency. Costs for the energy consultation itself are subsidised by BAFA at up to 80%, separate application possible.
- Step 2: Receive the BzA and submit the BAFA online application Once the BzA is in hand, head online to the BAFA portal. Application with BzA number, personal data, ownership details, planned system and the desired bonus stack combination. Anyone claiming the climate bonus must include a confirmation of the operability of the old heating system, typically through the installer or a chimney sweep certificate. Anyone applying for the income bonus must upload the previous year's income tax assessment. The application takes about 30 to 60 minutes online, depending on the completeness of the documents.
- Step 3: Wait for approval, then award the contract Processing time at BAFA is around 4 to 8 weeks as of May 2026, in peak times (late summer, shortly before the speed bonus deadline) also longer. Only after receiving the approval may the binding contract be awarded to the installer. Important: supply and service contracts may, prior to approval, only be concluded as preliminary contracts with a suspensive condition that explicitly references the funding commitment. Anyone who awards the contract firmly before the application is approved loses the full subsidy entitlement. Implementation deadline: 36 months after approval.
- Step 4: Proof of use and payout After completion of the system, the applicant submits the proof of use, with all invoices, commissioning protocol, final confirmation from the energy efficiency expert on the efficiency actually achieved and acceptance protocol from the installer. BAFA reviews and transfers the grant, typically within 6 to 12 weeks of receipt of all documents. With complete documents it often goes faster, with additional requests it can take considerably longer. Anyone using the KfW supplementary loan must service the KfW in parallel through their house bank, which runs formally separately from the BAFA payout.
An honest note: the entire process from the initial talk with the expert to the finished installation and the paid-out grant takes 8 to 18 months in practice. Anyone starting in 2026 is realistically done by 2027. This is not a horror scenario, it is the normal case. Anyone planning an emergency scenario because the heating fails should speak with the installer about pre-installation with a retrospective application, which is possible under very tight conditions but carries risks.
5. Common mistakes that lead to rejection
The BAFA rejection statistics for 2024 clearly show what most applications fail on. These five mistakes are the most common stumbling blocks, all avoidable with a bit of preparation.
- Building before applyingThe classic. Anyone who firmly awards the contract to the installer before the BAFA approval is in hand loses the entire entitlement. The funder argues: if the applicant has already awarded the contract, the funding is no longer an incentive but a windfall effect. As of May 2026 this rule was even tightened again. Solution: formulate a preliminary contract with a suspensive condition that explicitly references the funding commitment.
- Wrong efficiency value (SCOP below 3.0)Heat pumps with an annual performance factor below 3.0 are not eligible for funding. In old or poorly insulated buildings this is a real problem, because the SCOP in practice drops depending on flow temperature and heat distribution system. Solution: heat load calculation and hydraulic balancing BEFORE the system planning, possibly additional underfloor heating or larger radiators to lower the flow temperature.
- Hydraulic balancing missingThe BAFA subsidy requires hydraulic balancing per procedure B as a mandatory part. Without a documented balancing, rejection comes. The balancing is a technical adjustment of the heating system that secures the efficiency of the heat pump. Solution: the installer or a separate plumbing-and-heating company performs the balancing, the protocol goes with the proof of use to BAFA.
- Heat load calculation missingWithout a heat load calculation according to DIN EN 12831, no one knows how big the heat pump needs to be. Anyone who installs a system that is too small will not get the building warm in winter. Anyone who installs a system that is too large has unnecessary investment costs and poor part-load efficiency. Solution: the energy efficiency expert performs the calculation as part of the BzA preparation or requires it as a precondition.
- Missing technical minimum requirementsHeat pumps must meet certain minimum standards: sound pressure level in the outdoor area below 50 dB(A) at a distance specified in the LAI guidelines, refrigerant with a GWP value below 2,150, R32 or comparable, and since the 2024 reform additionally connectivity to digital control systems (smart meter gateway). Solution: check the product data sheets at the system manufacturer, BAFA has an official list of eligible systems.
Anyone ticking off these five points is on the safe path. The rejection rate at BAFA is overall below 10%, and almost all rejections can be traced back to one of these points. If in doubt, ask the energy efficiency expert specifically about it, they have that in their routine checklist. More on the overarching context of the CO2 levy, which additionally drives the switch to a heat pump economically, can be found in our glossary entry.
Plan your heating system replacement with the crisis scenario
Before you submit the application, work out once how much the next oil price jump will cost you if you wait. The energy cost calculator shows the crisis scenario in 60 seconds.
Start the energy shock calculator