Preliminary apartment sale contract: key clauses

A preliminary apartment sale contract is a key document when the purchase cannot be finalized immediately. It protects both parties, organizes the arrangements and allows calm preparation for the final contract — especially when a mortgage is involved. Below you will find practical tips on the most important clauses and how to avoid common mistakes.

Update: 5 March 2026

In brief:

• The more precise the description of the apartment and the deadline, the lower the dispute risk.
• A deposit and a mortgage require a realistic timeline.
• A notarial form increases security in larger transactions.

Preliminary contract when buying an apartment — when it is needed

It is most often signed when you need time to obtain financing, collect documents or agree on the date of transfer. In practice this is standard for mortgage‑financed transactions, but also for secondary‑market purchases where the legal status must be verified.

Reservation vs preliminary contract

A reservation agreement is often shorter and less binding, but it does not always provide real protection. If you want to secure the transaction, a preliminary contract with precise clauses is the safer choice.

What the apartment sale contract should include

Price, deadline, legal status, equipment

Solid clauses are the foundation of safety. The contract should include:

• precise identification of the parties and the apartment,
• price and payment method,
• deadline for signing the final contract,
• rules for handing over the apartment,
• information on the legal status and any encumbrances,
• a list of equipment that stays in the apartment.

It is also worth adding who prepares documents and which conditions must be met before signing the final contract.

Before signing, check the legal status of the apartment. In practice the key items are: the land and mortgage register, the seller’s title to the property, and any encumbrances. For cooperative apartments, additional documents confirming the right to the unit and no arrears in fees are required.

It is also good to determine whether anyone is registered in the apartment and whether any proceedings are pending that could hinder the transfer. Such information is worth including as parties’ declarations.

Describe the technical condition of the unit and what remains after sale. The more precise the list of fixtures and equipment, the lower the risk of misunderstandings at handover. A good practice is to attach a handover protocol or an equipment list as an appendix.

If the apartment requires repairs, indicate whether the seller commits to completing them before the final contract or whether the buyer accepts the current condition.

Specify when the handover will take place and how utilities will be settled. A good practice is to draw up a handover protocol and indicate who pays charges until the keys are handed over. These arrangements eliminate many disputes after the transaction.

Most common mistakes

The most common problems are:

• overly general deadline for the final contract,
• no precise description of the apartment and its legal status,
• unclear rules regarding the deposit,
• not accounting for the time needed for a mortgage.

Checklist before signing

• check the land and mortgage register and the title basis,
• set the final‑contract date with a buffer for the bank decision,
• specify equipment and technical condition,
• describe the handover rules and utility settlements.

Deposit and mortgage financing

A deposit is a popular form of security. It works differently from an advance payment, so clearly describe its amount, payment date and consequences of non‑performance. More on the differences can be found in the guide on deposit and withdrawal fee.

Mortgage and the final‑contract deadline

If the purchase is financed with a mortgage, set a realistic final‑contract date. In practice it is worth linking it to the credit decision and completion of bank documents. The guide on mortgage loans may help.

Notary and costs

Notarial fees and additional costs

A notarial form is not always mandatory, but in many situations it is the safest. It gives greater certainty about the effects of the contract and makes it easier to pursue claims. It is worth checking costs in advance, e.g. in the guide to notarial costs when buying an apartment.

If you are planning a purchase, see also the guides on total cost of buying an apartment and PCC for apartments.

Note: this text is for information only and does not constitute legal advice.