Purpose
The deposit is economically small and strictly regulated by law: any deviation to the detriment of the tenant is invalid under § 551(4) BGB. The two points of dispute in practice are the obligation to invest — it makes the deposit insolvency-proof and gives the tenant a right to withhold rent — and the settlement after return, for which the law expressly does not name a fixed deadline. This skill handles both cleanly and interlinks them with the short limitation period of § 548 BGB.
Inputs
- Deposit agreement: amount, form (cash deposit, guarantee, pledge, savings book), due date
- Net cold rent at the time of conclusion of the contract (reference figure for the maximum amount)
- Payment history of the deposit (instalments, dates)
- Proof of investment: account, separation from the landlord's assets, interest credits
- Return date of the rented property and return protocol
- Outstanding claims of the landlord: rent arrears, operating cost back payment, damages
- Whether the landlord has changed or compulsory administration or insolvency has occurred
Sub-agent architecture
The review is carried out in prose by specialised steps; this skill deliberately does not include a agentsblock (tenancy-law convention). An agreement reviewer checks the amount, form and instalment right and rejects clauses that are invalid under § 551(4) BGB. An investment reviewer examines the separate investment and the rights of the tenant arising from it. A settlement reviewer determines the time and scope of repayment as well as the scope of permissible withholding. A realisation reviewer clarifies against which claims set-off may be made. A limitation reviewer mirrors all landlord claims against the six-month period of § 548 BGB.
Process
1. Maximum amount and payment in instalments (§ 551(1), (2) BGB)
If the tenant is to provide security, it may not exceed three times the rent attributable to one month excluding operating costs — that is, three net cold rents —. A higher agreement is invalid to the extent of the excess; the additional amount must be repaid. The tenant is entitled to three equal monthly instalments ; the first instalment is due at the beginning of the tenancy, the further ones with the following rent payments. A clause requiring the deposit in full in advance is invalid under paragraph 4. The maximum amount applies to all Securities together — an additional surety alongside three net cold rents is generally inadmissible; otherwise in the case of a surety offered by a third party voluntarily and unsolicited .
2. Obligation to invest and protection in insolvency (Section 551(3) of the German Civil Code (BGB))
The landlord must invest a sum of money entrusted to him as security with a credit institution at the interest rate customary for savings deposits with a three-month notice period . The parties may agree on a different form of investment; in both cases the investment must be made separately from the landlord's assets . The income accrues to the tenant and increases the security.
The separation obligation is the core: it makes the deposit insolvency-proof — in the landlord's insolvency the tenant has a right to separate satisfaction, and in enforcement proceedings a right to object. If the landlord breaches the investment obligation, the tenant can demand investment and withhold the rent up to the amount of the deposit (Section 273 of the German Civil Code (BGB)); furthermore, damages may be considered. On the obligation of the compulsory administrator to surrender even where the deposit has not been passed on: German Federal Court of Justice (BGH), judgment of 09.03.2005 – VIII ZR 330/03, https://dejure.org/dienste/vernetzung/rechtsprechung?Gericht=BGH&Datum=2005-03-09&Aktenzeichen=VIII%20ZR%20330/03.
3. Forms of tenancy security
- Cash deposit — standard case; fully subject to Section 551(3) of the German Civil Code (BGB).
- Pledged savings book — in the tenant's name, pledged to the landlord; inherently satisfies the separation requirement.
- Surety (bank or private individual) — replaces the cash deposit; the investment obligation does not apply, the maximum amount continues to apply. Ensure that the defense of prior recourse is waived.
- Pledge of securities / deposit insurance — only by express agreement.
Agreements deviating to the tenant's detriment are invalid under Section 551(4) of the German Civil Code (BGB).
4. Default on the deposit and termination (Section 569(2a) of the German Civil Code (BGB))
A good cause within the meaning of Section 543(1) of the German Civil Code (BGB) also exists if the tenant is in default with a security under Section 551 of the German Civil Code (BGB) in an amount corresponding to two months' rent . Termination is excluded if the security is provided before the termination is received. A warning notice is unnecessary under Section 569(2a) sentence 2 of the German Civil Code (BGB). Further details: /mietrecht:fristlose-kuendigung-543.
5. Realization during the tenancy
The landlord may in principle during the ongoing tenancy not satisfy himself from the deposit — the security serves to provide protection at the end. Exception: claims established by final judgment or undisputed. If the landlord makes unjustified use of it, the tenant can demand replenishment. Conversely, the tenant may not to "live off" the last rent payments by offsetting them against the deposit — this constitutes payment default and a risk of termination.
6. Settlement after return
After termination and return of the leased property, the deposit must be settled and any surplus paid out. The law specifies no fixed deadline; the landlord is entitled to a reasonable period for consideration and review , which, depending on the scope of the settlement, is regularly set at three to six months . The tenant's claim for repayment only becomes dueupon expiry of this period. The landlord may retainpart of the deposit insofar as operating costs that have not yet been settled are to be expected — the amount retained must be based on the expected additional charge and must not be a flat-rate amount. After the statement is issued, the retained amount must be settled without delay.
7. Set-off and limitation (§ 548 BGB)
The landlord may set offdue counterclaims against the repayment claim: rent arrears, compensation for use under § 546a BGB, operating cost additional charge, damages for deterioration of the leased property. For claims for compensation for alterations or deteriorations , the six-month limitation period under § 548(1) BGB applies from return of the leased property. Set-off against a claim that is already time-barred is permissible under § 215 BGB if the claims were capable of being set off against each other at a time when the claim was not yet time-barred. The tenant's repayment claim is regularly subject to a three-year limitation period under §§ 195, 199 BGB. Further details on handling the return: /mietrecht:schoenheitsreparaturen-rueckgabe.
8. Change of landlord (§ 566a BGB)
If the leased residential property is sold, the purchaser steps into the rights and obligations arising from the security. It is liable to the tenant for return even if the deposit was not handed over to it; the transferor remains liable subsidiarily (§ 566a sentence 2 BGB). The tenant should therefore always assert claims against the purchaser and, in the alternative, also keep the transferor liable.
Sources
Statutes
- § 551 BGB, § 566a BGB, § 569 BGB
- § 548 BGB, § 546a BGB, § 215 BGB, § 273 BGB
- § 195 BGB, § 199 BGB, § 556 BGB (retention for operating costs)
Commentaries
- Blank, in: Schmidt-Futterer, Mietrecht, 15th ed. 2023, § 551 BGB marginal no. 1 et seq.
- Bieber, in: MüKoBGB, 9th ed. 2023, § 551 marginal no. 1 et seq.; § 566a marginal no. 1 et seq.
- Weidenkaff, in: Grüneberg, BGB, 84th ed. 2025, § 551 marginal no. 1 et seq.
Case law
- BGH, judgment of 09.03.2005 – VIII ZR 330/03 (obligation of the compulsory administrator to surrender even where the deposit was not forwarded) — verified: https://dejure.org/dienste/vernetzung/rechtsprechung?Gericht=BGH&Datum=2005-03-09&Aktenzeichen=VIII%20ZR%20330/03
- On the length of the accounting and consideration period after return and on the permissible retention of operating costs, the relevant BGH case law is to be consulted
[unverifiziert - prüfen]. - On the inadmissibility of an additional guarantee alongside the maximum deposit, the relevant BGH case law is to be consulted
[unverifiziert - prüfen].
Drafting aid — reclaiming the deposit after the end of the tenancy
Sehr geehrte Damen und Herren,
das Mietverhältnis über die Wohnung <Anschrift> endete am <Datum>. Die
Wohnung wurde am <Datum> übergeben; das Übergabeprotokoll liegt vor.
Ich habe zu Mietbeginn eine Barkaution in Höhe von <Betrag> EUR geleistet.
Seit der Rückgabe sind mehr als <…> Monate vergangen. Eine angemessene
Prüfungs- und Überlegungsfrist ist damit abgelaufen; der Anspruch auf
Rückzahlung ist fällig.
Ich fordere Sie auf, bis zum <Datum>
1. die Kaution nebst der nach § 551 Abs. 3 S. 3 BGB dem Mieter zustehenden
Zinsen abzurechnen und den Überschuss auf das Konto <IBAN> zu zahlen,
2. den Anlagenachweis vorzulegen (getrennte Anlage vom Vermietervermögen,
§ 551 Abs. 3 S. 3 BGB).
Etwaige Ersatzansprüche wegen Veränderungen oder Verschlechterungen der
Mietsache sind gemäß § 548 Abs. 1 BGB sechs Monate nach Rückerhalt, also
mit Ablauf des <Datum>, verjährt.
Ein Einbehalt für noch nicht abgerechnete Betriebskosten ist allenfalls in
Höhe der konkret zu erwartenden Nachforderung zulässig und der Höhe nach
zu begründen.
Mit freundlichen Grüßen
Output format
MIETSICHERHEIT § 551 BGB — Prüfung — <Mandat-ID> — <Datum>
I. Vereinbarung
- Form [Barkaution / Bürgschaft / Sparbuch / …]
- Höhe <Betrag> Nettokaltmiete: <Betrag>
- Höchstbetrag 3 Nettokaltmieten [gewahrt / überschritten um <Betrag>]
- Ratenzahlungsrecht (Abs. 2) [gewahrt / Klausel unwirksam § 551 Abs. 4]
II. Anlage (§ 551 Abs. 3) [getrennt angelegt / nicht nachgewiesen ❌]
Zinsen dem Mieter gutgeschrieben [✅ / ❌ <Betrag>]
Insolvenzfestigkeit [gegeben / gefährdet]
Zurückbehaltungsrecht § 273 BGB [nein / ja bis <Betrag>]
III. Kautionsverzug (§ 569 Abs. 2a) [N/A / Kündigungsrisiko ab 2 Monatsmieten]
IV. Rückgabe Datum: <…> Protokoll: [ja / nein]
V. Abrechnung nach Rückgabe Prüfungsfrist Ende: <Datum> [fällig / offen]
Einbehalt Betriebskosten <Betrag> [begründet / pauschal ⚠️]
VI. Gegenforderungen des Vermieters
- Mietrückstand / § 546a <Betrag>
- Betriebskostennachforderung <Betrag>
- Schadensersatz Mietsache <Betrag>
Verjährung § 548 BGB Ende <Datum> [offen / verjährt]
Aufrechnung § 215 BGB [möglich / ausgeschlossen]
VII. Vermieterwechsel (§ 566a) [N/A / Erwerber haftet, Veräußerer subsidiär]
VIII. Auszahlungsbetrag <Betrag> nebst Zinsen
Ergebnis: <…>
Risiko: [🟢 / 🟡 / 🔴]
Risks / typical mistakes
- Deposit not invested separately — the tenant may withhold rent under § 273 BGB, protection against insolvency is lost, damages may be claimed.
- Maximum amount exceeded — more than three net cold rents or an additional guarantee alongside the full deposit; the excess must be repaid.
- Right to pay in instalments excluded — the clause is invalid under § 551(4) BGB, but the deposit remains owed.
- Deposit used up — the tenant who offsets the last rents against the deposit falls into payment default and risks termination without notice.
- Limitation period under § 548 BGB overlooked — claims for compensation due to deterioration become time-barred six months after return; after that only § 215 BGB helps.
- Flat-rate retention of operating costs — the retention must be based on the specifically expected additional charge.
- Claiming the wrong party in the event of a change of landlord — under § 566a BGB the purchaser is primarily liable, the transferor only subsidiarily.
- Repayment demanded too early — before expiry of the reasonable review period the claim is not due; an action would have to be dismissed with costs.