Rental deposit calculator: how high may the deposit be?
Net cold rent and the deposit asked for are enough; add the start date and interest rate for instalments and interest.
Checked by Radif Partners · Editorial policy · Method
Maximum lawful deposit
€2,550
| Three instalments of | €850 |
| 1. instalment due | 1 November 2026 |
| 2. instalment due | 1 December 2026 |
| 3. instalment due | 1 January 2027 |
| Interest until move-out | €51.38 |
| Arrears that allow termination | €1,700 |
Interest belongs to the tenant and is added to the deposit (Section 551(3) BGB). Your deposit account statement shows the rate.
How we calculateA German rental deposit (Mietkaution) may be at most three times the monthly rent without the service charges shown as a flat rate or advance (Section 551(1) of the Civil Code). What counts is therefore the net cold rent (Nettokaltmiete). A cash deposit may be paid in three equal monthly instalments: the first at the start of the tenancy, the other two with the following rent payments. The landlord must keep the money separate from his own, in a bank account paying at least the usual rate for savings with three months' notice; the interest belongs to you and is added to the deposit. With net cold rent of €850, at most €2,550.00 is allowed, so three instalments of €850.00, due on 1 November 2026, 1 December 2026 and 1 January 2027. At 0.5 per cent interest over four years, €51.38 is added. If the landlord asks for €3,000, the agreement is void as to the €450.00 above the limit.
What the calculator checks
It multiplies your net cold rent by three and compares the result with the deposit demanded. If the demand is higher, the agreement is void only as to the excess; up to the limit it stands, and anything you overpaid can be reclaimed. With the start date it shows the three instalments that Section 551(2) BGB grants you. With your deposit account's interest rate it works out the interest to move-out, compounded, because the earnings are added to the deposit.
| Item | Value |
|---|---|
| net cold rent | €850.00 |
| maximum lawful deposit | €2,550.00 |
| instalment 1 on 1 November 2026 | €850.00 |
| instalment 2 on 1 December 2026 | €850.00 |
| instalment 3 on 1 January 2027 | €850.00 |
| interest at 0.5 per cent over four years | €51.38 |
| arrears limit for termination without notice | €1,700.00 |
How you can provide the deposit
The law assumes a sum of money but allows other forms if agreed: a savings book in your name pledged to the landlord, a bank guarantee or a deposit insurance. The three-month limit applies to all securities together. For student or youth halls the landlord need not pay interest. When and how you get the money back after moving out is on the deposit refund page; the principles are on the rental deposit page.