Partly, and the property itself answers for them. A buyer takes on the seller’s unpaid community charges for the elapsed part of the year of purchase plus the three previous calendar years. This is why a certificate of debt from the administrator is asked for at completion: it is the only way to see what you are taking on before you sign.
Where this comes from: art. 9.1.e Ley 49/1960 (LPH), BOE consolidated text, read 2026-09-10.