Upload your utility bill (Nebenkostenabrechnung / Betriebskostenabrechnung) — the AI checks every line item for admissibility and creates a ready-to-send objection letter if errors are found.
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Fictional example for illustration — not a real result.
Upload a PDF or photo of your utility bill — that's it.
Every line item is automatically checked for admissibility under German law.
Detailed report with inadmissible costs and a ready-to-use objection letter.
Every item is checked against the German Operating Costs Ordinance (BetrKV) — non-chargeable costs are flagged.
If errors are found, Mietlex instantly creates a legally secure objection letter ready to send.
Automatic check whether the landlord met the 12-month legal deadline (§ 556 BGB).
Uploaded documents and your analysis result are stored encrypted — deletable anytime on request.
The German Operating Costs Ordinance (BetrKV) lists exhaustively which costs are chargeable at all. Anything outside that list — plus two categories explicitly excluded — may not be passed on to you.
Explicitly not operating costs under § 1(2) No. 1 BetrKV — e.g. staff and overhead of the property management.
Repairs and refurbishment are likewise explicitly excluded under § 1(2) No. 2 BetrKV.
None of the 17 exhaustively listed operating cost categories in § 2 BetrKV cover this.
The financial risk of vacant units is borne by the landlord, not the remaining tenants.
Legal or court fees, e.g. to pursue claims against tenants, are not operating costs.
New bins, new technical systems or initial equipment are investment, not ongoing operation.
Property management compensation falls under non-chargeable administration costs.
The cost of preparing the bill is an administrative task of the landlord.
Postage for mailing the bill also counts as administration costs.
Setting aside reserves for future repairs isn't an operating cost actually incurred.
The utility bill is the annual statement of operating costs your landlord sends you. It shows what was actually incurred and offsets it against your advance payments. Many bills contain errors or inadmissible items.
Yes. Your uploaded bill and the analysis result are stored encrypted so you can access past checks anytime — under "My Utility Bill Checks". You can request deletion of your data at any time.
The AI detects non-chargeable costs (e.g. management fees, maintenance), incorrect distribution keys, missing receipts, inflated flat rates and missed deadlines. Studies show over 50% of all bills contain errors.
You receive a detailed report with all disputed items and the legal basis. Mietlex also automatically creates a ready-to-use objection letter you can send directly to your landlord.
You have 12 months after receiving the bill to object. If the landlord delivered the bill late (after 31 December of the following year), it is void. Mietlex checks both automatically.
The basic check with overall result is free. The full detailed analysis with all objections and the objection letter is paid.