A practical guide to reading price per square metre in Spain: asking price, deed price, reference value and cadastral value, and the area measures that change the result. General information, not legal advice.
This guide is general information, not legal advice. For a price, a tax, or a document in your own case, ask your own lawyer and your notario before you sign anything.
A price per square metre is a division: a price divided by an area. If either side of that division is unclear, the result is unclear too. Before you compare two homes by price per square metre, ask what price is being divided, and what area is being divided by. A guide that skips those two questions will mislead you even when every figure in it looks precise.
Spain has more than one price for a home, and they do different jobs. Do not treat them as interchangeable.
Asking price is the price a seller asks for. It is a starting point for negotiation, not proof of value and not what a home finally sold for. Deed price is the price recorded in the escritura before a notario. It is what the parties recorded at signing, and it belongs to a past transaction, not to a home that is on the market now. Valor de referencia is the reference value set by the Catastro. It is used as a minimum taxable base for transfer and other taxes. It is not an asking price and not a market valuation for a buyer. Valor catastral is the cadastral value used for annual taxes such as IBI. It is a fiscal value, not a sale price.
A Map Syndicat price per square metre reflects asking prices. It is not a deed price, not a valor de referencia, and not a valor catastral. Do not compare an asking average with a deed average as if they were the same series.
A flat has more than one area measure in Spain, and each one gives a different price per square metre for the same flat at the same price. Superficie útil is usable area, inside the outer walls. Superficie construida is built area, usable area plus walls. Superficie construida con partes comunes is built area plus a share of common areas.
A listing that uses a larger area will show a lower price per square metre than the same flat listed with a smaller area, even though the price has not changed. Before you compare, ask which measure a listing uses, compare like with like, and check the Catastro record for the property. A price without its area definition is not comparable.
Asking averages and deed averages can differ a lot, and the gap is not automatically a discount you can negotiate. Portal asking data describes homes that are on the market now, in the places where listings are active. Deed data describes homes that were sold and registered earlier, including stock that is no longer on the market. The two series also cover different periods: an asking figure is current, while a deed average can cover a longer past period. Treat the gap as a warning to check which series you are looking at, not as a price you can claim.
Spain also publishes official series, and each one measures change or transactions in its own way. The INE House Price Index is an index of change over time, not a price per square metre for a street or a district. The Colegio de Registradores statistics describe registered transactions. Portal indices describe asking prices. None of these is a Map Syndicat median, and none should be presented as if it were. If a source does not say which series it uses, do not use its figure to judge a single home.
Map Syndicat is a map platform: it gathers property listings from public sources in Spain and shows them on one map, with a link back to the original source. It sells nothing itself and takes no commission. When you find a home you like, follow the source link, re-check the original listing before you act, and contact the seller through that source, because prices and availability change at the source. Map Syndicat does not verify listing genuineness, photos, seller ownership, or current price or availability.
A median asking price per square metre on Map Syndicat is the middle asking figure in a set of asking listings. It is not a transaction price, not a certified index, and not a valuation of any single home. A median is useful for comparing areas at a glance, and it is weak for judging one home on its own, because condition, floor, light, building age, and exact street all sit inside the same median and are not shown by it.
A median is only as good as the set behind it. A small set, a set from one building type, or a set mixed across very different areas will give a median that looks precise and means little. If a median is shown without its area, its area measure, and its set, treat it as a prompt to look closer, not as an answer.
If any answer is unclear, pause and get that answer before you use the figure to decide. A price per square metre is a tool for comparison, not a verdict on a home.