Short answer. Yes. The Civil Code says in one line that an acceptance may be express or implied, so conduct can conclude a contract without anyone saying "I accept". What the conduct must show is a decision to take the offer exactly as it stands.

What the law says

An acceptance may be express or implied.

Civil Code, Article 1320 — Express or Implied Acceptance. Read the full provision →

The rule, and why it is written so briefly

Article 1320 provides simply that an acceptance may be express or implied. Philippine contract law is consensual at its core: a contract is perfected by the meeting of the offer and the acceptance on the object and the cause, and the Code does not prescribe magic words for either half. So a supplier who ships the goods described in a purchase order, a lessee who moves in and pays the agreed rent, a client who lets the work proceed on the quoted terms — each may have accepted, though none of them said so. The absence of a signature is not, by itself, the absence of a contract.

Conduct only counts if it is unequivocal

Implied acceptance is not loose acceptance. The act relied on must point clearly to a decision to be bound, and be consistent with nothing else. Continuing to negotiate is not acceptance. Studying a proposal, asking for time, or performing something you were already obliged to do proves nothing. Neither does silence: as a general rule a person who says nothing has not accepted, and an offeror cannot manufacture a contract by writing "if I do not hear from you I will assume you agree". Silence may acquire meaning where the parties' prior dealings or a trade practice gave it one, but the burden is on the person asserting the contract.

It must be acceptance of the offer as made

Whatever form it takes, the acceptance must be absolute. Article 1319 requires the acceptance to be unqualified; a qualified acceptance is a counter-offer, which kills the original offer instead of closing it. This matters for conduct, because part performance often reflects the party's own preferred terms rather than the offeror's. Delivering a smaller quantity, starting work on a different specification, or paying less than the price quoted is not implied acceptance of the offer — it is a new proposal that the other side is free to reject. The conduct has to match the offer, item for item, before it can perfect the contract described in that offer.

What this means in a live dispute

Two practical consequences. First, if you do not intend to be bound, do not begin performing while terms are still open; write that the work is without prejudice and pending a signed agreement. Second, if you are the one asserting that a contract exists, your case is built from the paper trail of behaviour — delivery receipts, deposit slips, site photographs, message threads showing instructions given and followed, invoices paid without protest. Certain agreements also have their own form requirements before they may be enforced or bind third persons, so implied acceptance does not cure every defect. Bring the full sequence of documents to counsel; in this area the order of events usually settles the question.

Cases citing this provision

These Supreme Court decisions cite the provision above. We list them so you can read them yourself; the summaries of what each decided are not ours to give.

Related provisions

Note. Statute text quoted on this page is reproduced from the official enactment and is linked to the full provision. The explanation around it is general legal information from Vivas & Nobles Law Office, not legal advice. Whether it applies to your situation depends on facts only a lawyer reviewing them can assess.