The contract states index rent (Indexmiete). Nevertheless, a higher monthly advance payment for operating costs is announced. That does not have to be a contradiction. The decisive factor is first which component of your total payment is to be changed and on what the declaration is based.
Break the monthly payment down into its components
Our editorial recommendation: place the contract, the most recent statement and the new letter side by side. Note the previous base rent and the separately agreed advance payments or flat rates. A single total on the bank statement does not show these differences. The heading Abschlag can also be imprecise; what matters is which contractual payment is actually meant.
Index rent is governed by the agreement and § 557b BGB. The provision contains requirements for a corresponding declaration and allows certain other changes separately. [INDEX] An index agreement therefore does not mean that every component of the total housing payment remains unchangeable.
Distinguishe between arrears and a new advance payment
A statement can result in an arrears payment for a past period. A changed advance payment, by contrast, concerns future payments. Section 560 paragraph 4 BGB enables, in the case of agreed advance payments for operating costs, an adjustment by declaration in text form to an appropriate amount after a statement. [BK] The specific statement and the appropriateness are therefore not automatically confirmed.
Check which basis the letter names. Is the stated statement available? Do period and dwelling match? Is it comprehensible how the new advance payment is justified? An enquiry should specify precisely the unclear point. If your contract provides for a flat rate instead of advance payments, you must not uncritically transfer the rule for advance payments.
An index declaration is a separate procedure
If the base rent is also changed, look for the corresponding declaration and its calculation. Do not confuse this with the justification for higher operating costs. Both procedures can affect your liquidity, but they should be understandable separately. Whether the form, timing and amount of a specific change are correct should be checked on the basis of the documents.
This article does not calculate an individual increase and does not state a current index value. That would require the appropriate published value together with the comparison date. A percentage taken from another case is not a reliable basis.
Example: Same base rent, different payment amount
In the fictitious example a household pays a base rent of 800 euros and an advance payment of 180 euros. After a statement an advance payment of 220 euros is demanded. The total monthly amount would thus rise from 980 to 1.020 euros, although the base rent remains the same. This simple example calculation proves neither the appropriateness nor the effectiveness of the actual letter. It only shows which component needs to be checked.
From understanding follows an appropriate mandate for review
Write down separately the questions regarding the statement, the advance payment and, where applicable, the base rent. This allows the responsible advisory service or the letting party to answer in a targeted way. For your budget planning note the demanded change and mark disputed points. Questions of deadlines and payment should, in case of uncertainty, be put into an individual review in good time, not into a blanket assumption about the word Indexmiete.