How we calculate prices

From the public Property Price Register, which records the amounts from notarial deeds. We get the data from Warsaw’s city map service.

No. A listing shows what the seller is asking. A notarial deed records what the flat sold for, and that’s the figure we show.

The property price: the flat plus whatever comes with it, such as a share of the land or a cellar. The register also gives a price for the whole transaction. That one can include, say, a garage sold in the same deed, so it’s sometimes higher.

Price per m² is the property price divided by the flat’s usable floor area.

Sort the prices from lowest to highest: the median is the middle of that list. One unusually high price doesn’t push it up the way it does the average. That’s why the map and charts show the median. A neighbourhood’s colour on the map is its median price per m².

No. The data only covers units within buildings, such as flats, garages and commercial units. We show flats by default; use the “Unit use” filter to add the rest.

We leave out sales where the price isn’t a market price for a whole flat:

• sales of a share, such as half a flat;
• sales at a statutory discount, such as a council flat sold to its tenant (the register has marked these since 2016);
• sales with no recorded price, or with a price under PLN 1,000 or under PLN 1,000 per m²;
• sales of units under 5 m².

It has fewer than 5 transactions under the current filters, and a median of so few sales jumps around too much. For the same reason a chart line is dashed for periods with fewer than 30 transactions.

Usually not yet. Deeds reach the register with a delay, so data for recent months is still coming in and the latest quarter’s median may change.

Yes, but with care. Up to 2015 the Warsaw register gives one price for the whole transaction: if a garage, say, was sold together with the flat, its price may be included, and there’s no way to check.

No. These are past sale prices. The data we get from the register doesn’t say what condition a flat was in, so two sales in the same building can differ quite a lot.