Mortgage for a Flat Under Construction in Poland 2026 – Tranches, Interest, Bridging Cover

The bank does not pay out a mortgage for a flat under construction at once, but in tranches – according to the schedule in the developer contract (umowa deweloperska), into the developer's housing escrow account (mieszkaniowy rachunek powierniczy). Until the last tranche is paid out you usually pay interest only, and only on the amount already drawn, and until the mortgage is entered in the land and mortgage register (księga wieczysta) the bank may add bridging insurance or a higher margin, which is refundable after the entry. Below we show step by step how this works and calculate the interest during construction for a flat from our offer completed in 2027.

Key facts

• Payments into an open housing escrow account follow the progress of construction – after successive stages of the schedule are completed (art. 8 of the Developer Act). The bank pays out loan tranches in the same way.
• Interest accrues only on the part of the loan drawn. In our example (loan PLN 598k, 6.07%) it is about PLN 16.6k during construction versus about PLN 27.2k if the whole loan were paid out at once.
• While tranches are being drawn, banks usually apply a grace period on principal repayment – you pay interest-only instalments; the full instalment (here about PLN 3 613) starts after the last tranche.
• An additional cost until the mortgage is entered (e.g. a margin higher by 0.5 pp) is refundable after the entry or credited towards repayment – art. 29 sec. 5a–5b of the Mortgage Act.
• The mortgage on the flat can be entered only after the contract transferring ownership; the court fee for entering a mortgage is PLN 200.

How a mortgage for a flat under construction works – tranches according to the schedule

When you buy a flat from a developer before the building is completed, you do not pay the whole price at once. The developer contract specifies the amount and dates of payments into the housing escrow account and the project schedule divided into stages (art. 35 sec. 1 points 9 and 12 of the Act on the protection of the rights of the buyer of a residential unit). You pay after a given stage is completed, and the developer is obliged to inform you of this on paper or another durable medium (art. 8 sec. 3).

The bank matches loan drawdowns to this schedule: the loan agreement will contain a tranche schedule, and each successive tranche goes to the escrow account named in the developer contract, not to you or to the developer's ordinary account. With an open escrow account, the bank running the account releases the money to the developer only after confirming that a stage has been completed and no earlier than 30 days from the conclusion of the developer contract (art. 16 sec. 1). More about how payments are protected and what role the Developer Guarantee Fund plays can be found in the article Escrow account and the DFG.

Before paying out the next tranche, the bank usually checks the progress of construction – on the basis of a notification from the developer, an inspection or a report. For example, the model mortgage agreement of Bank Ochrony Środowiska provides for the next tranche to be paid out within 7 days of a correct application and for a property inspection before each tranche, and where there is a discrepancy with the schedule the bank may withhold payment until it is resolved. The details depend on the bank, so the tranche schedule is worth reading as carefully as the developer contract.

The down payment usually goes towards the first instalments

The bank finances part of the price (most often up to 80%), and you cover the rest yourself. In practice this means that the first payments from the schedule – at signing and after the first stage – are made from your own money, and the bank joins in later. A condition for paying out the first tranche is often precisely documenting that you have paid in your own funds in the amount specified in the loan agreement (this is the case, among others, in the model BOŚ agreement mentioned). If the first instalment to the developer falls right after the contract is signed and the credit decision has not yet been made, you must have the down payment “at hand” earlier. How much of it you need and where to get it we describe in the guide to the down payment.

Interest during construction – an example for a flat completed in 2027

Let us take a real flat from our offer: 2 rooms, 39.14 m² in the Metro Art 14 development in Praga-Południe, price PLN 747 574 (PLN 19 100/m²), completion in the fourth quarter of 2027 – based on TM Invest offer data as of 27.09.2026. We assume a 20% down payment (PLN 149 515), a loan of PLN 598 059 over 30 years and an interest rate of 6.07% – the average for new zloty housing loans in July 2026 according to NBP. The payment schedule is illustrative; you will find the real one in the developer contract for the given development.

Month from contract	Stage (example)	Payment	Source	Loan drawn after payment	Monthly interest
0	Signing the developer contract	PLN 74 757 (10%)	down payment	–	–
3	Open shell stage	PLN 74 758 (10%)	down payment	–	–
6	Closed shell stage	PLN 224 272 (30%)	1st tranche	PLN 224 272	about PLN 1 134
10	Installations and plastering	PLN 224 272 (30%)	2nd tranche	PLN 448 544	about PLN 2 269
14	Completion of construction	PLN 149 515 (20%)	3rd tranche	PLN 598 059	about PLN 3 025
Interest until handover (month 15)				about PLN 16 638

How we calculated it: the first tranche works for 9 months (PLN 224 272 × 6.07% × 9/12 ≈ PLN 10 210), the second for 5 months (≈ PLN 5 672), the third for 1 month (≈ PLN 756). In total about PLN 16.6k. If the bank paid out the whole loan in one go in the 6th month, interest until handover would be about PLN 27.2k (PLN 598 059 × 6.07% × 9/12) – more than PLN 10k higher. After the last tranche is paid out, repayment of principal begins: an equal instalment over 30 years will be about PLN 3 613. How the instalment changes for other amounts and terms, you will see in the mortgage instalment tables.

Remember the other side of the budget: during construction you usually still pay for your current home – rent or the instalment of an old loan. Over 15 months with rent of PLN 3 000, that is another PLN 45k, more than the loan interest.

Want to align the tranche schedule with the developer's schedule before you sign the contract? Book a consultation with a mortgage expert – we will compare offers from several banks for a loan in tranches: the grace period, security until the mortgage is entered and payout dates.

Grace period on principal repayment during construction

A grace period on principal repayment means that for a set time you pay interest only, and you start repaying principal later. For a mortgage on a flat under construction this is the typical solution for the period when tranches are drawn – the interest instalment rises with each tranche (in our example PLN 1 134, then PLN 2 269 and PLN 3 025), and the full principal-and-interest instalment starts after the whole amount has been drawn.

The rules differ between banks, so check them in the documents, not in advertising. For example, in Santander Bank Polska's general information on mortgages, loans paid out in tranches are covered by a grace period on principal repayment until the last tranche is paid out; on request the bank may extend it up to 6 months after the last tranche, though the grace period in total will not exceed 36 months from the start of the loan, and you pay interest on the amount used throughout. Extra months of grace period after handover can help with fitting out, but they lengthen the period in which you do not repay principal – and so they increase total interest.

Bridging insurance for a mortgage – what it is and how much it costs

The ultimate security for the loan is a mortgage on your flat. When buying off-plan it does not exist yet: the unit becomes a separate property with its own land and mortgage register only upon the agreement establishing separate ownership and transferring it to you, and then the court still has to make the entry. For this period the bank applies interim (bridging) security. It can take several forms:

• a higher margin or interest rate until the mortgage is entered – commonly called “bridging insurance”,
• bridging insurance bought by the bank from an insurer, the cost of which is passed on to the borrower,
• assignment of rights under the developer contract and to the funds in the escrow account to the bank – at no additional cost to you.

The law does not specify how much bridging security may cost – each bank sets this itself and states it in its general information, representative example and ESIS form (the standardised European information sheet). Below are examples from banks' public documents (as of the dates given in the documents):

Bank and document	Security until the mortgage is entered	Cost
Santander Bank Polska – general information on the rules for granting mortgages (compilation of lender documents from 03.2026)	higher margin (variable rate) or higher interest rate (fixed rate), only when the loan is drawn without a filed and paid application for the mortgage entry	+0.50 pp; refund of interest within 30 days of notification of the entry
BNP Paribas Bank Polska – representative example of 19.01.2023	higher margin until the date the mortgage is entered	+1.00 pp (in the example: PLN 1 962.91 for a loan of PLN 338k and an assumed 7 months)
Bank Millennium – general information on the mortgage agreement (example of 05.03.2026)	for a flat from a developer: assignment of rights under the construction contribution, covering payments to the developer and funds in the escrow account	the document does not list a higher margin among interim security

What it costs in our example

Suppose the bank raises the interest rate by 0.5 pp from the first tranche until the mortgage is entered. If you sign the deed transferring ownership 2 months after handover, and the court enters the mortgage after another 3 months (entry in the 20th month from the developer contract), the additional cost will be about PLN 2.6k. With a six-month delay (entry in the 26th month) – about PLN 4.1k. This is money you pay as you go, but get back after the mortgage is entered.

Refund of bridging insurance after the mortgage is entered

Since 17 September 2022 the Mortgage Act has regulated this cost directly. The agreement may provide for an additional cost of the loan connected with waiting for the mortgage to be entered in the land and mortgage register (art. 29 sec. 5a), but after the entry it is refundable to the consumer or credited towards repayment of the loan, on the terms set out in the agreement (art. 29 sec. 5b). The deadline and method of refund are therefore set by the bank in the agreement – in the cited Santander Bank Polska document it is 30 days from notification of the entry.

In practice the provision makes bridging insurance today more a liquidity problem than a cost: for several to a dozen or so months you pay a higher instalment, and after the entry the money comes back. Still, it is worth shortening this period – because it is your money frozen in the bank, and with a long developer delay the amount grows. How to compare offers on such costs in the ESIS we describe in the article Which bank for a mortgage.

Entering the mortgage after the transfer of ownership – how not to prolong the interim period

After handover of the flat you sign the contract transferring ownership at a notary's office. Often in the same deed you also establish a mortgage in favour of the bank. The notary files the application for entry in the land and mortgage register electronically, at the latest on the day the deed is drawn up (art. 92 § 4 of the Notaries Act). The court fee for entering a mortgage is PLN 200 (art. 42 of the Act on court costs in civil cases), and the entry has retroactive effect – from the moment the application is filed. You will find the full list of purchase fees in the article Court fees and the land and mortgage register.

• Align the dates: check whether the date of the transfer of ownership in the developer contract fits within the period the bank assumed in the loan schedule.
• Prepare the documents for the bank in advance: an extract of the deed, the number of the new land and mortgage register and the flat insurance policy with assignment. You will find the list in the article Documents for a mortgage.
• After the entry make sure the bank knows about it – in some agreements the deadline for refunding the higher margin is counted from notification of the entry.

What if the developer is late?

A delay in construction shifts everything: successive tranches, the end of the grace period, the deed transferring ownership and the mortgage entry. There are three consequences for the loan. First, you pay interest on the tranches already drawn for longer, and rent for your current home at the same time. Second, the interim period lasts longer, and so does, for example, the higher margin (refunded only after the entry). Third, the loan agreement has its own schedule and deadline for using the funds – shifting tranches may require an annex, and banks may charge a fee for it under their tariff.

If the developer does not transfer ownership by the date in the contract, the Developer Act gives you the right to withdraw – after setting an additional period of 120 days (art. 43 sec. 1 point 6 and sec. 3). The funds released from the escrow account are then returned within 30 days (art. 44 sec. 3), but with a loan in tranches the decision has to be coordinated with the bank, because it financed part of the payments. That is why, even before signing the contract, it is worth checking the developer and its schedule – the guide how to check a developer will help.

Flats under construction in our offer

A loan in tranches applies to most new flats. According to TM Invest offer data as of 27.09.2026, of 4 351 available flats in Warsaw and Wroclaw as many as 3 250 (about 75%) are in developments under construction – 57 developments, of which 26 have a completion date in 2027 (about 1 360 units). There are 1 101 completed flats that you can buy with a loan paid out in one go. See the offers in Warsaw and in Wroclaw.

Frequently asked questions

Summary

A mortgage for a flat under construction is a loan paid out in tranches into the escrow account, in line with the progress of construction. You pay interest only on the amount drawn, you usually start repaying principal after the last tranche, and until the mortgage is entered the bank may apply more expensive bridging security, which it refunds after the entry. The biggest risk is the schedules getting out of step and the developer being late – so the dates in the developer contract and the loan agreement are worth comparing before signing both. We describe the whole process in the guide Mortgage step by step.

Buying a flat with completion in a year or two? Book a consultation with a mortgage expert – we will compare offers from several banks for a loan in tranches, calculate the interest during construction and the cost of security until the mortgage is entered. We have operated since 2016 on the market in Warsaw and Wroclaw.

Legal status as of September 2026. The calculations are indicative, the payment schedule is illustrative, and the banks' terms come from their public documents and may change. The article is not an offer or financial advice; the final terms and the credit decision are determined by the bank.

Sources

• Act of 20 May 2021 on the protection of the rights of the buyer of a residential unit or single-family house and on the Developer Guarantee Fund, Dz.U. 2026 item 880 – art. 5, 8, 16, 35, 43, 44
• Act of 23 March 2017 on mortgage credit and on the supervision of mortgage credit intermediaries and agents, Dz.U. 2025 item 720 – art. 29 sec. 5a–5b
• Act on court costs in civil cases, Dz.U. 2025 item 1228 – art. 42 sec. 1
• Act on land and mortgage registers and mortgages, Dz.U. 2026 item 1066 – art. 29, 67
• NBP – MIR interest rate statistics, new residential real estate loan agreements in PLN (July 2026)
• General information on lenders' mortgage agreements (compilation from 03.2026) – documents of Santander Bank Polska, BNP Paribas Bank Polska, the BOŚ model agreement (in Polish)
• Bank Millennium – General information on the mortgage agreement (representative example of 05.03.2026) (in Polish)
• Notaries Act (Prawo o notariacie), Dz.U. 2026 item 614 – art. 92 § 4
• Flat prices: TM Invest development catalogue, as of 27.09.2026