In the Italian real estate market, the phase preceding the preliminary contract is often governed by atypical or “practice” negotiation instruments, which, however, assume a far from secondary legal importance.
Among these, the irrevocable purchase proposal and the LOI – letter of intent (or expression of interest) are frequently confused, with the effect of exposing the parties to unintended constraints or, on the contrary, to overstated protections.

The distinction is not only theoretical: it concerns when the obligation to sell or buy arises, what remedies are actionable, and what damages can be claimed in case of second thoughts.

1. The irrevocable purchase proposal: what it is and why it is dangerous if underestimated

1.1 Normative foundation and practical function

The irrevocable purchase proposal is governed by Article 1329 of the Civil Code, which allows the offeror to unilaterally bind himself to hold his offer firm for a specified period.
In the real estate industry, it is used primarily to:

• “freeze” the buyer’s interest;

• To allow the seller a comparative evaluation;

• Anticipate the future stipulation of the preliminary.

1.2 From proposal to preliminary: the point of no return

The most recent case law is extremely clear:
when the irrevocable proposal contains all the essential elements of the future contract and is accepted by the seller, it becomes a preliminary contract for all purposes.

According to numerous substantive 2024-2025 decisions, the proposal is not a “neutral act” if it contains:

• party identification;

• property description;

• price and mode of payment;

• deadline for deed;

• provision for down payment;

• indications of urban conformity and absence of detrimental constraints.

In such cases, the seller’s acceptance-once known to the proposer-determines the creation of a full contractual bond, with application of the rules on the preliminary, including the possibility of action under Article 2932 of the Civil Code.

1.3 Irrevocability and expiration of the time limit

The period of irrevocability is essential in nature.
Case law has clarified that:

• If the seller accepts after the deadline, the acceptance is equivalent to a new proposal;

• If, on the other hand, acceptance occurs in a timely manner, the lien automatically arises.

This profile is often ignored in real estate agency practice, with the risk of disputes over timeliness and communication of acceptance.

2. The LOI (letter of intent): a flexible instrument, but not without effect

2.1 Economic and legal function of LOI

The LOI was created to regulate the pre-contractual phase, especially in complex or high-value transactions (commercial real estate, investments, real estate portfolios).
It serves to:

• Fix the points already shared;

• Organizing due diligence;

• Scan the stages of the negotiation;

• Avoid parallel negotiations.

Unlike the irrevocable proposal, the LOI does not aim for the immediate conclusion of the deal, but for its progressive construction.

2.2 When the LOI is NOT a preliminary.

Case law clearly distinguishes LOI from preliminary contract when:

• Lacks an explicit obligation to sell or buy;

• the price is only indicative;

• further negotiations are planned;

• the operation is subject to technical or financial verification.

In such cases, the LOI remains a pre-contractual act, with no direct translative or binding effects.

2.3 Binding clauses within a “non-binding” LOI.

Beware, however: an LOI may contain individual legally binding clauses, including:

• confidentiality obligations;

• exclusivity or “no shop” clauses;

• cost allocation;

• penalties for unjustified withdrawal;

• forum and applicable law.

Merit case law has recognized the validity and enforceability of penalties stipulated in LOIs when the breakdown of negotiations is contrary to commitments made

3. Irrevocable proposal and LOI compared: substantive differences

4. Effects of default and liability

4.1 Non-performance of the accepted irrevocable proposal

If the proposal turned into preliminary:

• rules on security deposit apply;

• it is possible to apply forspecific enforcement;

• the compensable damage is full.

4.2 Breakdown of negotiations after an LOI

In the case of LOI, the protection is different:

• Article 1337 Civil Code (pre-contractual good faith) operates;

• compensation is limited toadverse interest;

• any agreed-upon penalties can be triggered.

The LOI, therefore, does not compel buying or selling, but it does compel proper dealing.

5. Operational directions: which tool to choose?

When to prefer the irrevocable proposal

• negotiation already mature;

• Willingness to freeze the property;

• Agreement on all essential elements.

When to prefer LOI

• complex operations;

• Need for due diligence;

• Willingness to maintain negotiating flexibility.

In both cases, the technical drafting of the document is decisive: many disputes arise not from the instrument itself, but from ambiguous clauses or standardized forms.

Conclusions

The irrevocable purchase proposal and the LOI are not mere “antechambers” of the preliminary, but autonomous legal instruments with profoundly different effects.
To confuse them is to expose oneself to:

• Unintended contractual constraints;

• Avoidable litigation;

• Significant economic responsibilities.

In the modern real estate market, the real protection is not the speed of signing, but the legal awareness of the stage you are in.

L'articolo Irrevocable purchase proposal vs LOI (letter of intent) in the real estate market: differences, effects and risks proviene da Studio Legale Mauro.