Checking Your Utility Cost Statement: The Most Common Errors and How to Spot Them

Short answer: Ancillary costs are only owed if they are explicitly and individually listed in the lease agreement – a blanket formula such as "customary ancillary costs" is not sufficient according to the Federal Supreme Court. Under Art. 257b para. 1 CO, only costs actually incurred may be charged, with no profit margin for the landlord. Tenants have a right to inspect supporting documents under Art. 257b para. 2 CO.

What Can Actually Be Charged?

The legal basis for ancillary costs is found in Art. 257a and 257b CO. What matters first is whether and how the individual items are listed in the lease agreement: if a concrete list is missing, or if the contract merely refers in general terms to "customary ancillary costs," these costs are not owed at all according to Federal Supreme Court case law. In addition, the cost-coverage principle applies under Art. 257b para. 1 CO: only costs actually incurred may be charged, and a profit margin for the landlord is not permitted.

Costs that cannot be passed on include, in particular:

• Repairs, maintenance, and renewal of installations, as well as their interest and depreciation – this is the landlord's responsibility and is already included in the net rent
• General property management costs
• Building insurance premiums

One important nuance concerns administrative costs: the costs of preparing the utility cost statement itself may be charged, with the usual rate being 3.5 to 4.5 percent of the total ancillary costs (around 0.5 percent less for gas heating systems, since the preparation effort is lower there). General property management, on the other hand – i.e., the overall administrative oversight of the property – is legally disputed. The Federal Supreme Court has not yet issued a definitive ruling on this, which means differing views exist depending on the canton and the individual case.

The Most Common Errors in Practice

Media reports and spot checks by tenant associations suggest that a significant proportion of statements contain errors. However, there is no reliable, representative statistic on this – the percentages circulating should therefore be treated with caution. Regardless of the exact frequency, checking is worthwhile, since the following types of errors keep recurring:

• Incorrect allocation keys (e.g., by floor area instead of the contractually agreed measure)
• Items not agreed in the contract that are charged anyway
• Excessive heating and hot water costs compared to the previous year or reference values
• Repairs or investments incorrectly declared as ancillary costs
• Inflated electricity rates that exceed the actual procurement costs

Deadlines: What Happens If I React Too Late?

There is no statutory deadline for disputing a utility cost statement. Many lease agreements do contain a contractually agreed deadline, often 30 days – however, this is not binding, and a later objection generally remains possible. What matters instead are the statutory limitation periods: additional claims by the landlord become time-barred after 5 years, while tenants can reclaim overpaid amounts for up to 10 years.

The 10-Point Checklist for Reviewing Your Statement

This checklist lets you work through a utility cost statement systematically:

1. Are all items individually and comprehensibly listed in the lease agreement?
2. Compare with the previous year's statement – are there any noticeable deviations?
3. Is the allocation key (floor area, number of occupants, consumption) clearly documented and plausible?
4. Does the statement include repair, maintenance, or investment costs? (not permitted)
5. Does it include general administrative costs (not permitted), or only the costs of preparing the statement (permitted, approx. 3.5–4.5%)?
6. Were building insurance or property owner taxes charged? (not permitted)
7. Were the advance payments made correctly deducted?
8. Were supporting documents requested or reviewed (a right under Art. 257b para. 2 CO)?
9. Were the heating costs compared with the previous year or reference rates?
10. Is the objection made in writing, with payment of the disputed amount "subject to reservation" until the matter is clarified?

Frequently Asked Questions

Conclusion

Ancillary costs are not a given: they must be contractually agreed, actually incurred, and correctly allocated. Anyone who applies the 10-point checklist, requests supporting documents, and disputes any unclear points in writing is on solid legal ground – even without a statutory deadline looming.

All figures and legal references in this article are disclosed and linked → Sources.