The Importance of Buyer Due Diligence in Real Estate Transactions and the Obligations of the Parties

20 de November de 2025

The sale and purchase of real estate often give rise to disputes when, once the contract has been perfected, the buyer discovers circumstances concerning the property that were unknown at the time of acquisition. This article examines the scope of the seller’s liability and the degree of diligence the buyer is expected to exercise before signing, as well as the legal consequences of failing to do so.

 

The relevance of acting diligently in real estate purchases

 

It is relatively common for disagreements to arise when the purchaser discovers, after the transaction, previously unnoticed encumbrances, urban planning restrictions, or characteristics of the property that were not disclosed. If these circumstances are explicitly stated in the contract, the possibility of making a claim is practically non-existent. However, when they do not appear in the contract, a key question arises:

 

Should the seller be held liable? And what if the information was available in public records and the buyer could have consulted it?

 

The Supreme Court has addressed this issue on numerous occasions. In Judgment 1139/2006, of 17 November, the Court established that the principle of good faith in contractual relations does not require the seller to provide information that can be accessed through public sources. It further explains that good faith also requires the buyer to act prudently and to carry out reasonable checks before acquiring the property.

In other words, the seller is not obliged to reproduce information already available in the Land Registry or to explain the applicable urban planning regulations, since both are accessible to anyone who consults them. The seller’s duty to inform is limited to facts not recorded in public sources or to circumstances that contradict the official records.

 

Urban planning: what happens if restrictions are not mentioned?

 

In Judgment 155/2011, of 16 March, the Supreme Court reaffirmed that limitations arising from urban planning regulations do not automatically entitle the buyer to rescind the contract merely because they were not mentioned. What is decisive is assessing:

  • whether the buyer could have become aware of these limitations, and
  • whether the buyer acted with the diligence required.

Therefore, the buyer must, at the very least, carry out basic checks: consult the land registry information, review the applicable urban planning regulations, and, if necessary, request an urban planning certificate from the relevant town council. This document is essential for determining building restrictions or other relevant limitations affecting the property.

 

What the seller must disclose and what the buyer must verify

 

Obligations of the seller

 

  • Communicate any information that cannot be obtained through usual public sources.
  • Disclose encumbrances or situations not recorded in public registers or that contradict the official records.

Obligations of the buyer

 

  • Consult the Land Registry.
  • Review the applicable urban planning regulations.
  • Verify the urban planning conditions using available means (including the urban planning certificate).
  • Act with the diligence expected from someone undertaking a financially significant transaction.

If the buyer fails to carry out these checks, it will be difficult to successfully claim later for a price adjustment or request the termination of the contract.

Additionally, the intervention of a real estate agency does not exempt the buyer from acting diligently, as noted in Judgment 118/2021 of the Provincial Court of Barcelona, dated 22 February.

 

Conclusion

 

Prevention is essential in real estate transactions. Obtaining legal advice from the outset and carefully reviewing all documentation and the contract can prevent most of the disputes that commonly arise in this type of transaction.