This page covers German rental law and may not apply to you.
CO₂ cost split for landlords. The German CO₂-Kostenaufteilungsgesetz (CO₂ cost allocation) is a country-specific law that splits the carbon-price burden between landlord and tenant via a 10-tier energy-efficiency model. It is a federal German statute introduced in 2023.
In your country, the closest regulation is MEES Regulations.
Rentprime is also available for United Kingdom with localised templates and billing logic. The relevant local regulations are pre-configured — you don’t need this German-specific topic.
CO₂ costs finally split correctly.
Since 2023 German landlords must contribute to CO₂ costs — the worse the building's energy balance, the higher the landlord's share. Rentprime calculates this automatically using the 1–10 tier model with the official emission factors of the BMWK (German Ministry of Economic Affairs).
How much does this really cost you?
Two real scenarios — once an efficient building, once a renovation case. See the difference in euros.
Which level does your building fall into?
Slide the CO₂ emissions per square metre per year — and instantly see which of the ten levels your building falls into and how the costs split between you and your tenant.
| Tier | kg CO₂ / m² · year | Tenants | Landlord |
|---|---|---|---|
| 1 | < 12 kg | 100 % | 0 % |
| 2 | 12–17 kg | 90 % | 10 % |
| 3 | 17–22 kg | 80 % | 20 % |
| 4 | 22–27 kg | 70 % | 30 % |
| 5 | 27–32 kg | 60 % | 40 % |
| 6 | 32–37 kg | 50 % | 50 % |
| 7 | 37–42 kg | 40 % | 60 % |
| 8 | 42–47 kg | 30 % | 70 % |
| 9 | 47–52 kg | 20 % | 80 % |
| 10 | ≥ 52 kg | 5 % | 95 % |
Which fuel produces how much CO₂?
The official BMWK values (German Ministry of Economic Affairs) — Rentprime uses them automatically in every calculation.
Natural gas
0,201 kg/kWhHeating oil
0,266 kg/kWhDistrict heating
0,221 kg/kWhLPG
0,234 kg/kWhWood pellets
0,038 kg/kWhHeat pump
0,105 kg/kWhSix levers for less CO₂ self-contribution.
Every measure moves you down tiers — saving you significant money long-term. The most economically attractive steps:
Practical tip: Even a hydraulic balancing (cost €500–800) brings 5–15% efficiency and typically pays back within 2 years.
The CO₂ Cost Act explained simply — and what it means for you as a landlord
Since 1 January 2023, the German Carbon Dioxide Cost Allocation Act (CO₂ cost allocation) has been in force. It governs how the CO₂ costs arising from the Brennstoffemissionshandelsgesetz (BEHG) are split between landlord and tenant. Previously, the tenant bore the entire heating costs including the CO₂ surcharge — today the landlord's share is determined according to the building's energy efficiency.
The logic: the worse a building is insulated and the older the heating, the higher the CO₂ emissions per square meter — and the more the landlord must pay. Anyone living in a KfW-40 house pays the full CO₂ share as tenant; anyone living in an unrenovated 1960s building pays only a small part. The CO₂ price rises every year: €30/t in 2023, €40 in 2024, €50 in 2025. The landlord share therefore gets more expensive over the years — even at the same consumption.
Important: If you do not split the CO₂ share correctly and charge the tenant more than permitted, the tenant can reclaim that share — the deadline is 12 months from receipt of the bill. Intent or gross negligence may also incur fines per § 11 BEHG. With Rentprime you have a documented calculation you can produce in a dispute.
Special case heritage protection: If energy refurbishment cannot be carried out due to public-law regulations, a reduction of the landlord's share by up to 100% can be applied for (§ 9 CO₂ cost allocation). Rentprime stores these special cases in the property profile and applies them automatically.