Online Chat Agreements as Binding Contracts under Article 1320 of the Indonesian Civil Code

Artikel ini ditulis oleh Nadira Zahra Faisal dan Nathania Ilona Akhmad

Background and Problem Formulation

In recent years, digital communication has become widely used as a medium for individuals to communicate, negotiate, or even form agreements in both personal and professional contexts.¹ What once was exclusively done through face-to-face meetings or formal written documents, has shifted into informal chat threads, instant messaging, social media, and other online platforms. This development reflects a broader transformation in how parties express consent and create legal relationships through electronic means.² The question arises: when two parties exchange promises via online chat, do those promises carry binding force as a “contract” in the sense of Indonesian contract law? Especially within the framework of Book III in the Indonesian Civil Code, one key provision is Article 1320 which sets out the conditions for the validity of an agreement.

According to Article 1320, an agreement is valid if it fulfills (i) the consent of the parties, (ii) capacity of the parties to make the binding commitment, (iii) a definite object, and (iv) a lawful cause. In traditional settings, proof of these often depended on formal documents, signatures, and clear contractual drafting. In the digital context, some practitioners and scholars question whether chat-based promises (often informal, quick, and lacking paper signatures) can meet these requirements and produce binding obligations.

Moreover, the advent of electronic contracts in Indonesia under the framework of Law Number 11 of 2008 on Electronic Information and Transactions (“ITE Law”) and Government Regulation Number 71 of 2019 on the Operation of Electronic Systems and Transactions adds an important legal dimension.³ These instruments expressly recognise that electronic transactions and electronic contracts are binding upon the parties provided that they meet the essential elements of a valid agreement and comply with statutory requirements. However, a critical question arises: when parties exchange promises merely through chat messages, for instance does it become binding and instantly enforceable or it depends on what kind of agreement is made on an online chat?

Analysis

Indonesia’s private law itself adheres to the pluralistic system where regulations are mainly derived from Indonesian Civil Code which is derived from European law by the Netherlands with hints of customary law that grows beyond society since time immemorial, also affected by the religious law as a state where the main philosophical values is adhered to the value of the almighty God. So as the contract law in Indonesia, which is a part of private law sectors, regulations about contracts are referring from those three sources. However Indonesian Civil Code is the only written legal source for Indonesian private law sectors which is generally accepted while customary law and religious law provides principles and normative rules in the policy making related to private law in Indonesia and some of it only applies to some people who believe in certain religions and traditions itself.

Practically there are several names and types of agreements as a part of social activities starting from daily transactions to common interactions between people. As there are many different types and names of agreements and contracts, Article 1319 of the Indonesian Civil Code provides clear regulations about it in which there are two types of agreements regulated in it such as nominaat agreements and innominaat agreements. Nominaat agreements are an agreement that has a specific name and whose provisions are regulated in civil law or other relevant laws, meanwhile inominaat agreements are agreements that arise, grow, live, and develop in society that is not being regulated by the Indonesian Civil Code however it is regulated in the relevant laws and regulations.

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We use many types of named agreements every day as a part of our daily routine without realizing it, such as Buying and selling, Bartering, Renting, Work agreements, Civil partnerships,Grants, Custody of goods, Lending, Borrowing, Authorization, Fixed or perpetual interest, Profit-sharing agreements, Debt guarantees, Peace agreements, and Prenuptial agreements. On the other side, types and namings of inominaat agreements in the Civil Code, in practice there are several types of agreements which are often categorized as anonymous agreements like franchise agreements, leasing agreements, joint ventures agreements, and so other agreements beside the nominaat agreements that have been sorted amongst Book III of the Indonesian Civil Code. Although both are regulated formally, albeit in different regulations, nominaat agreements have more benefits rather than innominate agreements because they provide more legal certainty, avoid the risk of confusion in the event of a dispute, minimize other risks, increase credibility, etc. Nevertheless innominate agreements also contend with special superiority such as flexibility. Although the legal consequences of an innominate agreements are the same as those of a nominaat agreement, namely that it is binding and legally enforceable as long as it meets the requirements for a valid agreement (agreement, capacity, certain matters, and a lawful cause). If any of these requirements are not met, the agreement may be void by law or have no legal consequences. Furthermore, if a breach occurs, the injured party may sue for damages or fulfillment of obligations in accordance with general civil law provisions.

As the Indonesian Civil Code offers many different types and names of agreements, it still has general regulations regarding agreements that applies generally to each type and name of agreement where the making of the regulations are influenced by general legal principles and principles. Indonesian contract law is grounded in consensualism, freedom of contract, and binding force of contract (pacta sunt servanda). These principles, inherited largely from Dutch civil law traditions, remain preserved in Book III of the Civil Code, particularly in Articles 1320 and 1338.

1. The Principle of Consensualism in Digital Contexts

Under the principle of consensualism, an agreement is formed the moment parties reach mutual consent regardless of form. Article 1320 establishes that the first element of a valid agreement is the consent of those binding themselves. Indonesian law does not require a particular form unless otherwise regulated (e.g., land transfer, marriage, or wills). Therefore, the method of communication, whether oral, written, or electronic does not inherently invalidate consent.

Indonesian courts have, in various cases involving electronic evidence, accepted chat logs, emails, and digital messages as valid proof of consent when sufficiently authenticated. The ITE Law, particularly Article 5, expressly 3 recognizes electronic information and electronic documents as lawful evidence equivalent to traditional written evidence.

Thus, when two individuals exchange clear, unequivocal promises via chat such as agreeing on price, object, and intention to be bound, a strong argument exists that the consensual element under Article 1320 is satisfied.

2. Capacity of the Parties

The second element under Article 1320 concerns the legal capacity (cakap hukum) of the parties. The digital nature of communication does not alter the substantive rules governing capacity. Adults who are not under guardianship possess full legal capacity to form agreements, whether through formal contracts or digital chats.

One practical challenge concerns identity verification. Chats do not inherently guarantee the identity of the person behind the device. However, this issue relates more to proof than to validity. The ITE Law and GR 71/2019 emphasise authentication, which can be established through:

• Phone number ownership;
• Platform verification (e.g., registered email);
• Two-factor authentication;
• Metadata;
• Digital signatures (for more formal transactions).

Thus, the capacity requirement is generally satisfied as long as the parties are legally competent, and evidence supports the authenticity of the parties involved.

3. A Certain Object

The third condition under Article 1320 requires a specific object. Chat agreements can easily satisfy this element as long as:

• The object is clearly described (e.g., “iPhone 12, 128 GB”, “renting my apartment for one month”, “freelance design services”);
• The price or compensation is stated, and
• The obligations of both parties are identifiable.

Where chat agreements tend to fail is when messages are vague, ambiguous, or incomplete, for example:

• “I think it’s going to happen.”
• “It’s possible, depends on you.”

Such expressions do not indicate intent to be bound and instead represent preliminary negotiations. In contract doctrine, these fall under “invitation to treat” rather than “offer and acceptance”. Therefore, not all chats constitute contracts; only those with sufficiently defined terms meet the requirement of a “certain object.”

4. Lawful Cause

The final element of Article 1320 concerns the “lawful cause”, meaning that agreements must not violate law, morality, or public order. Chat agreements being merely a medium do not change this substantive rule. A chat-based transaction to sell illegal goods or engage in unlawful acts is void regardless of its digital form.

5. Article 1338 and the Binding Force

Article 1338 KUH Perdata provides the foundational principle, “Every agreement lawfully made shall bind the parties as law.” This implies that once an agreement fulfils Article 1320 requirements, it becomes binding like law between the parties. Because Indonesian law recognises electronic documents and communication as valid evidence, a chat agreement once meeting all the essential elements can indeed carry binding force.

Importantly, no provision in Indonesian law mandates that a contract must be physically signed unless the law explicitly requires a specific form. Consequently, chat agreements are not merely informal or social exchanges; they can be legally enforceable binding contracts.

The ITE Law, particularly Articles 18 to 20, expressly recognises electronic contracts as instruments that carry binding and enforceable legal force. This legislative framework is reinforced by Government Regulation No. 71 of 2019, which requires that electronic transactions be supported by verifiable identities, accessible content, and a demonstrable expression of consent in electronic form. These provisions mirror the principles found in international instruments such as the UNCITRAL Model Law on Electronic Commerce, which Indonesia has effectively adopted in spirit. As a result, the modern regulatory environment strongly supports the legitimacy of electronic contractual formation, including agreements concluded through chat platforms. Nevertheless, the ITE Law does not create a distinct legal category for chat-based agreements. Instead, all forms of electronic communication whether email, messaging applications, or platform-based interactions are treated as electronic information that may serve as valid evidence. Consequently, the enforceability of chat agreements continues to depend on the requirements set out in the Civil Code, with Article 1320 serving as the primary benchmark for evaluating validity in a digital context.

A central analytical issue involves differentiating chat exchanges that constitute binding agreements from those that amount only to preliminary discussions or casual communication. A binding agreement exists when the parties’ messages clearly demonstrate an offer, an acceptance, and a mutual intention to create legal obligations. In contrast, preliminary negotiations reflect an exploratory stage in which the parties discuss possibilities without committing themselves, and social correspondence consists of everyday informal expressions devoid of any legal intent. In practice, Indonesian courts assess these distinctions by examining the clarity of the terms used, the parties’ apparent intention to be bound, the factual circumstances surrounding the conversation, the conduct of the parties after the exchange, and the internal consistency of the messages. A decisive statement such as “Deal. I will transfer today,” may indicate a clear intention to conclude an agreement, whereas an expression like “I’ll text you later” conveys hesitation and an absence of binding commitment.

In addition to the binding and regulating power of a message, it depends on the content of the conversation whether it gives rise to a bond that becomes an agreement, whether the agreement can then be classified as a nominaat or innominate agreement, in the case that the agreement is included in the classification of an innominate agreement, are there any regulations governing about how binding and enforce could it be, and the classification of the agreement is what will then further determine the validity, legal force of an agreement, and whether it causes any legal consequences or not.

Although the legal foundation for recognising chat agreements is firmly established, their enforceability ultimately depends on evidentiary reliability. Courts frequently rely on materials such as screenshots, exported chat logs, timestamp records, cloud backups, and where necessary expert testimony from digital forensic specialists. These forms of digital evidence must collectively demonstrate that the conversation occurred as claimed, that the messages were not manipulated, and that the individuals involved actually used the accounts or devices in question. The evidentiary process may also require proof that the consent expressed in the chat was not obtained through deception, coercion, or technical interference. Thus, even when a chat exchange satisfies the substantive requirements of Article 1320, the success of a claim still turns on the authenticity and integrity of the electronic evidence presented before the court.

Conclusion

The increasing use of digital communication has transformed the way individuals interact, negotiate, and form agreements. Within Indonesian contract law, the essence of a binding agreement under Article 1320 of the Civil Code remains unchanged: consent, capacity, a definite object, and a lawful cause. These fundamental elements apply equally to agreements formed through online chat, provided that the parties clearly express their intention to be legally bound. The ITE Law and GR 71/2019 further reinforce the validity of electronic contracts by recognising electronic messages as legitimate means to express consent and as admissible evidence within judicial processes.

However, the informal nature of chat communication often makes it difficult to distinguish between binding commitments, preliminary negotiations, and purely social exchanges. The absence of formal language or clear contractual structure requires courts to rely heavily on interpretive factors such as the clarity of terms, contextual circumstances, and subsequent conduct of the parties. Furthermore, while chat agreements may be substantively valid, their enforceability ultimately depends on the types of agreements whether it is nominaat or innominate agreements and how it causes the legal consequences and so it depends on can it be used as a digital evidence. Challenges such as possible message manipulation, identity verification, and incomplete documentation underscore the central role of technological reliability and forensic support in disputes involving chat-based agreements.

Overall, Indonesian law does not reject the validity of chat agreements; rather, it integrates them into existing contractual doctrine. Yet the practical complexities surrounding intent and proof mean that parties must approach digital communication with caution when undertaking legal commitments.

Suggestion

First, legislators and policymakers should consider issuing clearer guidelines or regulatory provisions specifically addressing chat-based agreements within the broader framework of electronic contracts. While the ITE Law recognises electronic communications in general, explicit guidance on the evidentiary and interpretive standards for chat agreements would enhance legal certainty and reduce ambiguity in practice.

practice.
Second, courts and practitioners should continue to develop consistent judicial standards for interpreting intent in digital communication. These standards may include indicators such as explicit acceptance, definitive terms, chronological message context, and post-chat conduct. A more uniform approach would help distinguish legally binding commitments from casual expressions and thereby promote fairness and predictability in dispute resolution.

Third, individuals and businesses should adopt prudent communication practices when negotiating or agreeing to obligations through chat platforms. To avoid ambiguity, parties should use clear and unequivocal language when they intend to form a contract. Where appropriate, parties should follow up chat-based commitments with more formal documentation or electronic signatures to strengthen evidentiary value.

Finally, digital literacy and awareness should be increased among the public to ensure that individuals understand that even informal chat messages may carry legal consequences. As the boundary between social communication and contractual formation becomes increasingly blurred in the digital age, a more informed society will be better equipped to navigate the legal implications of online interactions.

1. Rouse, “Indonesia: Electronic Contract Best Practises,” Rouse Insight, 2022, https://rouse.com/insights/news/2022/indonesia-electronic-contract-best-practices ↩︎
2. Schinder Law Firm, “The Legal Aspect of Electronic Agreements in Indonesia,” Schinder Law Blog, https://schinderlawfirm.com/blog/the-legal-aspect-of-electronic-agreements-in-indonesia/ ↩︎
3. Law of the Republic of Indonesia No. 11 of 2008 on Electronic Information and Transactions, as amended by Law No. 19 of 2016. ↩︎