Utility billing create yourself — Step by step.

What a utility billing must contain

A proper utility billing — even Operating cost statement called — must contain the following minimum information per Federal Court of Justice case law:

• Accounting period (exact dates from … to …)
• Total costs of the management unit per cost type
• Allocation key per type of cost (e.g. living area, persons, consumption)
• Pro-rata cost for the individual tenant
• Tenant's advance payments made
• Balance (back payment or refund)
• For heating costs: split per German heating regulation § 7 (consumption + area)
• Since 2023: CO₂ allocation under CO₂ cost allocation with tier classification

If one of these mandatory entries is missing, the tenant can declare the billing as formally invalid reject (Federal Court of Justice). You'd have to correct and resend — an avoidable time-waster.

Step 1: Collect and assign receipts

Throughout the year you collect all invoices related to the rental property: heating bill from the energy supplier (e.g. British Gas, OVO Energy), water bill, property tax notice, insurance premium, caretaker, waste fees, chimney sweep, garden maintenance, elevator.

Important: Separate allocable from non-allocable costs. Admin costs, maintenance and repairs, bank fees and tenant search costs may NOT be allocated. With Rentprime you mark these automatically — when entering you choose the cost type, and the software knows if it's allocable.

Step 2: Set distribution key

For each cost type, you must apply the distribution key from the lease — or, if nothing agreed, the legally prescribed one:

• Living area (m²): standard for property tax, insurance, garden maintenance
• Number of units: waste, caretaker, common electricity, elevator
• Number of persons: water costs (where measurement is not consumption-based)
• Consumption: heating and water (where meters are present) — mandatory under §556a Abs. 2 BGB
• German heating regulation § 7: heating with 70% consumption + 30% area (or 50/50, 60/40)

Step 3: Heating costs per German heating regulation §7

Heating and hot water are a special case: at least 50%, max 70% must be split by consumption. 70/30 is recommended — creates the strongest saving incentive for tenants and reduces the landlord's own CO₂ share via the CO₂ cost allocation.

Since 2022, consumption-measuring devices must fernablesbar be (German heating regulation). Existing devices must be retrofitted by end of 2026. Failure risks tenants reducing heating costs by 15% (German heating regulation).

Step 4: CO₂ split since 2023

The CO₂ Cost Allocation Act requires since 1 January 2023 that landlords share the CO₂ portion of heating costs. The tier depends on CO₂ output per m² and year — for natural gas the emission factor is 0.201 kg CO₂/kWh, for heating oil 0.266 kg/kWh.

Example: 78 m² apartment, gas heating, annual consumption 12,000 kWh. CO₂ output = 12,000 × 0.201 = 2,412 kg. Per m²: 2,412/78 = ~31 kg CO₂/m²/a. That's tier 5 → landlord 40%, tenant 60%.

Step 5: Mind the deadline — German Civil Code

The billing must be done within 12 months after the end of the billing period reach the tenant. For calendar-year billing (1 Jan – 31 Dec 2024) you must therefore have delivered by 31 Dec 2025. Not sent on time means: additional payment claim lost — credit balances still have to be paid out though. zugegangen.

Miss the deadline? Then you can no longer claim additional payment. You must still pay credit balances to the tenant. An expensive lesson many landlords learn once.

Step 6: Document delivery

Send the billing by registered mail or hand over in person (with receipt). In dispute you must prove that and when the tenant received it. A simple email is only enough if explicitly agreed in the lease.

With Rentprime you can do the delivery via the Tenant portal document — the tenant logs in, picks up the bill, the software records date and time audit-proof.

Common errors and how to avoid them

• Administration costs in the allocation — not apportionable, a frequent cause of objection
• Wrong distribution key — e.g. water by area instead of persons
• Heating split outside the 50–70% range — invalid
• CO₂ tier forgotten or miscalculated — tenant can reclaim
• Deadline missed — back payments lost
• Receipts not offered for inspection — duty per German Civil Code
• Costs of tenant search or vacancy allocated — not permitted

Software vs Excel vs tax advisor

Three options for creation:

• Excel template: free, but error-prone and time-consuming — 4–12 hours per property per year
• Tax adviser: 30–80 € per statement, but legally compliant
• Software wie Rentprime: ab 15,90 €/Monat (5 Einheiten) — automatische Berechnung, Updates bei Gesetzesänderungen, KI-Belegerkennung

For 1–3 units Excel can still pay off. From 4 units or with limited time, software is almost always cheaper and safer — especially if you don't want to track CO₂ Act and German heating regulation changes annually.