Madrid: read both portals before you sign (August 2026 numbers)

Two portals publish "the" price per square metre for Madrid. Same month, same district, and they do not agree. That gap is where a newcomer gets hurt.

Sale prices, August 2026:

- Villaverde: 3,302 €/m² (idealista) vs 3,062 €/m² (fotocasa). 240 €/m² apart, about €16,800 on a 70 m² flat.

- Puente de Vallecas: 216 €/m² apart. Carabanchel: 185. Centro: 42. The two indexes nearly agree in the centre and split widest in the cheapest districts.

Rents sit closer (Carabanchel: 19.1 vs 19.05 €/m² a month), so for rent the trap is different: the ask vs what tenants actually sign. A 60 m² flat quoted €1,800 a month in a district whose index says about 19 €/m² is a €1,140 flat with a hype premium. Do the multiplication before you negotiate.

Three checks before trusting a listing:

1. Pull the same barrio on both portals. If the gap is big, the price is a claim, not a fact.

2. Multiply by the metres and compare with the ask.

3. The portal where you found the flat is not a neutral referee.

If you are weighing a specific district or flat right now, say which below and I will pull the same two-portal numbers for it.