Preliminary Agreement for the Sale of a Flat – Deposit, Form, Deadlines

A preliminary agreement for the sale of a flat (umowa przedwstępna) obliges the seller and the buyer to conclude the sale agreement itself (the final agreement) in the future, on terms already agreed. It can be an ordinary written agreement or take the form of a notarial deed – and the form decides whether, in a dispute, you can force the sale in court or can only claim damages. Below we explain how a deposit (zadatek) differs from an advance payment (zaliczka), how much deposit is customary, how to word a mortgage clause and what happens to the money in typical scenarios – using the example of a flat for PLN 700 thousand.

Key facts

• A preliminary agreement must set out the essential terms of the sale agreement – at least the flat and the price (Art. 389 § 1 of the Civil Code, "KC").
• Only an agreement in the form of a notarial deed allows you to claim in court that the final agreement be concluded; with an ordinary written one, only damages remain (Art. 390 § 1–2 KC).
• Claims under a preliminary agreement become time-barred one year after the day on which the final agreement was to be concluded (Art. 390 § 3 KC).
• A deposit is forfeited if the buyer withdraws, and if the seller withdraws – the buyer may demand twice the deposit (Art. 394 § 1 KC). An advance payment is, as a rule, refundable.
• A preliminary agreement and a deposit are not subject to PCC (civil law transactions tax); the tax (2% on the secondary market, unless an exemption applies) arises only on the agreement transferring ownership.

What is a preliminary agreement and when is it worth signing?

In a preliminary agreement one or both parties undertake to conclude a specified agreement in the future (Art. 389 § 1 KC). For the sale of a flat this is standard, because it is rarely possible to sign the deed straight after agreeing the price. The buyer is waiting for a mortgage, the seller – for the bank's consent to delete the mortgage, or for certificates. The preliminary agreement "freezes" the price and terms for that time.

The seller is protected against a buyer who changes their mind after two months, and the buyer – against a sale to someone who offers more. The place of the preliminary agreement in the whole process is described in the guide selling a flat step by step.

Preliminary agreement at a notary or in writing?

An agreement obliging one to transfer ownership of real estate should take the form of a notarial deed (Art. 158 KC), but the preliminary agreement itself may also be concluded in ordinary written form – it is then valid, but produces weaker effects. The difference is shown by Art. 390 KC:

Issue	Written form	Notarial deed
What you can do if the other party refuses to sign the sale agreement	claim compensation for the loss you suffered in reliance on the agreement being concluded (e.g. valuation, commission, rental costs)	demand in court that the final agreement be concluded – a final judgment replaces the other party's declaration – or damages
Entry of the claim in the land and mortgage register	no	yes – a claim for transfer of ownership can be disclosed in the register (KW, court fee PLN 150)
Cost	no official fees	notary's fee + 23% VAT + copies (example below)
For whom	simple transactions, quick deadline, cash	longer deadline, high deposit, purchase with a mortgage, seller with an encumbered register

The buyer's claim disclosed in the register is effective also against persons who would later acquire rights to the flat (Art. 17 of the Registers Act) – with a high deposit, it is the best protection.

How much does a notarial preliminary agreement cost?

The regulation on maximum rates of notarial fees does not mention a preliminary agreement expressly. The starting rate is the full rate from § 3 (§ 5), and half is due, among other things, for an agreement creating an obligation concluded under a condition or with a time-limit clause (§ 6 pt 1) – the classification is determined by the notary. For a price of PLN 700 000 the rate under § 3 is PLN 1 010 + 0.4% of the excess over PLN 60 000, i.e. PLN 3 570 net (PLN 4 391.10 with VAT); half is PLN 1 785 net (PLN 2 195.55 with VAT). These are maximum rates – ask the notary's office for a quote in advance. Who pays is agreed by the parties; more on the rates in the article notary fees.

Deposit vs advance payment – what is the difference?

A deposit is governed by Art. 394 KC: if the agreement is not performed through the fault of one party, the other may, without setting an additional deadline, withdraw from the agreement and keep the deposit received, or, if it was the one who paid it, demand a sum twice as high. If the agreement is performed, the deposit is credited towards the price. If the parties terminate the agreement by mutual consent, or nobody is at fault (or both parties are), the deposit is returned and the obligation to pay the double amount lapses (Art. 394 § 3).

An advance payment has no separate regulation in the Code – it is simply part of the price paid in advance. If the sale does not take place, it is, as a rule, refundable regardless of who is at fault; any loss must be claimed under the general rules. That is why an advance payment disciplines the parties poorly. Write "deposit" (zadatek) in the agreement outright – wording such as "an amount as security" breeds disputes.

Deposit on the sale of a flat – how much?

The regulations do not set the amount of the deposit. In market practice about 10% of the price is often seen, but that is custom, not a norm – the parties may agree on less or more. A buyer with a mortgage should check with the bank how the deposit will be accounted for within the down payment. With too low a deposit (e.g. 1–2%) it is easy to "buy yourself out" when a better offer appears.

Example: a sale for PLN 700 thousand, deposit PLN 70 thousand – what happens to the money?

Assumptions: the seller and the buyer sign a notarial preliminary agreement, the price is PLN 700 000, the deposit PLN 70 000 (10%), the final agreement is due in 3 months, and the agreement contains a mortgage clause. For comparison we show what would happen if the same PLN 70 000 were paid as an advance payment.

Scenario	Deposit PLN 70 000	Advance payment PLN 70 000
Sale agreement concluded on time	credited to the price – the buyer pays the remaining PLN 630 000	credited to the price – the buyer pays the remaining PLN 630 000
The buyer withdraws without a valid reason	the seller may withdraw and keep PLN 70 000	PLN 70 000 refunded to the buyer; the seller may claim damages if they show a loss
The seller withdraws (e.g. received a higher offer)	the buyer may withdraw and demand PLN 140 000 (their own PLN 70 000 + PLN 70 000) or – with a notarial deed – demand in court that the agreement be concluded	PLN 70 000 refunded; further claims – damages or (with a deed) court-ordered conclusion of the agreement
The bank refuses the mortgage, mortgage clause satisfied	PLN 70 000 refunded, with no further claims	PLN 70 000 refunded
The bank refuses the mortgage, no mortgage clause	risk of dispute: the seller may argue that non-performance is attributable to the buyer and keep PLN 70 000; the buyer may rely on Art. 394 § 3	PLN 70 000 refunded
Termination of the agreement by mutual consent	PLN 70 000 refunded (Art. 394 § 3)	PLN 70 000 refunded

A deposit works symmetrically: if after signing an offer PLN 50 thousand higher appears, breaking the agreement still costs the seller PLN 70 thousand.

Do you want to sell your flat without being left with an unsigned agreement and a buyer without a mortgage? Order a valuation and sale plan – we will help prepare and carry out the sale, from setting the price to the date at the notary.

What if the buyer does not get a mortgage? The mortgage clause

The bank usually issues its credit decision only after receiving the preliminary agreement. Without an appropriate provision, a refusal of the mortgage does not automatically release a party from the agreement, and a dispute over whether the buyer "is responsible" for the lack of financing is resolved by the court. A good mortgage clause answers several questions:

• By when the buyer must obtain a credit decision and within what time they will notify of a refusal.
• How many banks are to be approached (e.g. applications filed with at least two or three banks) and for what loan amount – so that the buyer cannot "order" a refusal by applying for an unrealistic amount.
• How to prove the refusal – a copy of each bank's written refusal decision.
• What then – the right to withdraw from the agreement within a set period (Art. 395 KC) and refund of the deposit in full within a set number of days.

In return the seller may stipulate that the clause does not apply if the buyer did not file applications on time or withdrew from the procedure on their own initiative. Tailor the wording of the clause to the deadlines of the specific transaction. If you are selling a flat that is encumbered with a mortgage, also read how selling a flat with a mortgage works – there we explain how the repayment reaches your bank.

Deadline for the final agreement – what does the law say?

A popular myth goes: "a preliminary agreement is valid for a year". In fact the one-year period from Art. 389 § 2 KC applies only where the parties did not state at all a deadline for concluding the final agreement. Then the entitled party sets the deadline, and if nobody does so within a year of signing the preliminary agreement, its conclusion can no longer be demanded. Where the agreement contains a deadline, that deadline applies.

The second important period is limitation: claims under a preliminary agreement become time-barred one year after the day on which the final agreement was to be concluded (Art. 390 § 3 KC). If the other party evades, do not delay with a lawsuit. In practice it is worth stating a specific date (or "no later than…") with a margin for the mortgage procedure, the seller's bank's consent to delete the mortgage, and gathering the documents.

What to put in a preliminary agreement for the sale of a flat?

The minimum is the parties, the flat and the price (Art. 389 § 1). A good agreement settles in advance the matters the parties argue about most often:

• Parties – all owners (including a spouse under joint property) and attorneys.
• The flat – address, area, land register number (KW), type of title, cellar, parking space.
• Price and payment – amount, deposit, deadline and method of paying the rest, the part from the mortgage.
• Legal status and encumbrances – mortgages, easements, tenancy; an undertaking to delete the mortgage (e.g. repayment from the price straight to the seller's bank).
• Deadlines – date of the final agreement, date of handover of the flat, handover protocol with meter readings.
• Registration of residence – an undertaking to deregister all persons no later than the handover date.
• Fittings – a list of what stays (kitchen, appliances, wardrobes), ideally as an annex.
• Mortgage clause, contractual penalties for delay in handover (e.g. an amount for each day of delay) and the split of notarial costs.

You confirm some of this information with documents that you prepare before the notary – the list is in the article documents for selling a flat. When selling through an agency, the agreement is usually prepared by the broker – see selling through an agency or on your own.

Preliminary agreement vs developer agreement and reservation agreement

Different rules apply on the primary market. An agreement with a developer in which it undertakes to build a unit or to transfer its ownership is subject to the Developer Act and must take the form of a notarial deed (Art. 40 sec. 1 of the Act), and payments go into an escrow account – details in the article developer agreement. In turn, a reservation agreement with a developer is not a deposit: the reservation fee may not exceed 1% of the price from the information prospectus (Art. 32 sec. 2).

This matters when you are selling an old flat to buy a new one. According to TM Invest offer data as at 27.09.2026, for up to PLN 700 thousand there are 557 new flats available in Warsaw and 843 in Wroclaw; the median price of a 2-room flat is PLN 755 824 in Warsaw and PLN 662 405 in Wroclaw. It is worth aligning the date of the final agreement for the sale of the old flat with the developer's payment schedule – we describe four ways to do this in the article how to buy a new flat while selling the old one. When buying from a developer, our help with buying a flat is in most cases with no commission for the buyer – the developer usually pays our fee.

Is PCC or income tax paid on a preliminary agreement?

No. The closed catalogue of transactions subject to PCC (Art. 1 sec. 1 of the Act) includes the sale agreement, but not a preliminary agreement or a deposit. Where a sale is preceded by an agreement creating an obligation, the tax liability arises only at the moment the agreement transferring ownership is concluded (Art. 3 sec. 2). It is paid by the buyer: 2% of the price, unless they are entitled to an exemption when buying a first flat – more in the article on PCC tax on buying a flat.

The seller does not pay PIT (personal income tax) on the preliminary agreement itself – the revenue arises on the onerous disposal, i.e. the final agreement. If you are close to the five-year limit from acquisition, set its date deliberately; the rules for counting the period are explained in the text on tax on selling a flat within 5 years.

Frequently asked questions

Summary

With a high deposit and a longer deadline, choose a notarial deed, call the payment a deposit, state a specific date for the final agreement and describe the scenario of a mortgage refusal. Remember the one-year limitation period – counted from the day on which the sale agreement was to be signed.

Selling a flat in Warsaw or Wroclaw? Order a valuation and sale plan – we will help prepare and carry out the sale. If you are buying a new flat at the same time, before signing we will check the developer or reservation agreement.

Legal position as at September 2026. The calculations are indicative, and the article is not legal or tax advice – it is worth consulting the content of a specific agreement with a notary or lawyer.

Sources

• Civil Code, consolidated text Dz.U. 2026 item 795 – Art. 158, 389, 390, 394, 395
• Act on Tax on Civil Law Transactions, consolidated text Dz.U. 2026 item 191 – Art. 1 sec. 1, Art. 3 sec. 2, Art. 7 sec. 1
• Regulation of the Minister of Justice on maximum rates of notarial fees, consolidated text Dz.U. 2024 item 1566 – § 3, § 5, § 6
• Land and Mortgage Registers Act, consolidated text Dz.U. 2026 item 1066 – Art. 16, 17
• Act on Court Costs in Civil Cases, consolidated text Dz.U. 2025 item 1228 – Art. 43
• Act on the Protection of the Rights of a Purchaser of a Dwelling or Single-Family House and on the Developer Guarantee Fund, consolidated text Dz.U. 2026 item 880 – Art. 2, 32, 40
• Flat prices: TM Invest investment catalogue, as at 27.09.2026