Business Laws and Ethics · Indian Contracts Act, 1872

Nature and Essentials of a Valid Contract

Updated 10 October 2026 · Fact-checked

A contract is an agreement enforceable by law (Section 2(h)). An agreement is a set of promises forming consideration for each other (Section 2(e)). To answer, test the facts against each essential: offer and acceptance, consideration, capacity, free consent, lawful object, certainty and possibility. Then name the result: valid, void or voidable.

Understand Nature and Essentials of a Valid Contract

Start with the chain of definitions in Section 2. A proposal is made when you signify your willingness to do or not do something, to get the other person's assent. When that person assents, the proposal is accepted and becomes a promise. Every promise, and every set of promises that form the consideration for each other, is an agreement.

Not every agreement is a contract. Section 2(h) says an agreement enforceable by law is a contract. So: Contract = Agreement + enforceability by law. All contracts are agreements, but not all agreements are contracts. A promise to meet a friend for dinner is an agreement, but no court will enforce it.

For an agreement to become enforceable, it must satisfy certain essentials. From the sections of the Act, these include: a proposal and its acceptance; consideration (Section 2(d), Section 25); parties competent to contract; free consent; a lawful object; and meaning that is certain or capable of being made certain (Section 29). The agreement must also not be void for other reasons, such as restraint of trade (Section 27) or mutual mistake of fact (Section 20). Two further points from general contract law are an intention to create legal relations, and the formalities (such as writing or registration) where a law requires them.

The Act also classifies agreements by their legal effect. A void agreement is not enforceable by law (Section 2(g)). A voidable contract is enforceable at the option of one or more parties, but not at the option of the other or others (Section 2(i)). A contract that ceases to be enforceable becomes void when it ceases to be enforceable (Section 2(j)). A valid contract meets all the essentials and is fully enforceable.

Finally, the Act itself: Section 1 gives the short title, the Indian Contract Act, 1872. It extends to the whole of India and came into force on the first day of September, 1872. Usage or custom of trade, and incidents of a contract, are saved if they are not inconsistent with the Act.

Key rules to remember

Agreement: Agreement = Promise + Promise forming consideration for each other (Section 2(e)); Every promise and every set of promises forming the consideration for each other is an agreement.
Contract: Contract = Agreement enforceable by law (Section 2(h)); All contracts are agreements; not all agreements are contracts.
Void agreement: Agreement not enforceable by law = void (Section 2(g)); Void from the start. Compare Section 2(j): a contract that later ceases to be enforceable becomes void then.
Voidable contract: Enforceable at the option of one party, not the other (Section 2(i)); Valid until the entitled party chooses to avoid it.
Consideration: Act or abstinence or promise, at the desire of the promisor, by the promisee or any other person (Section 2(d)); Without consideration an agreement is void, unless one of the exceptions in Section 25 applies.
Exceptions to no consideration, no contract (Section 25): (1) written, registered, natural love and affection between near relations; (2) promise to compensate for something already voluntarily done; (3) written, signed promise to pay a time-barred debt; Also, Explanation 2: inadequate consideration does not make an agreement void if consent was freely given.
Uncertainty and impossibility: Meaning not certain or capable of being made certain = void (Section 29); act impossible in itself = void (Section 56); Section 20: both parties mistaken about a fact essential to the agreement makes it void. Wrong opinion about value is not such a mistake.
Restraint of trade: Agreement restraining a lawful profession, trade or business is void to that extent (Section 27); Exception 1: seller of goodwill may agree not to carry on a similar business within specified local limits, if the Court finds the limits reasonable.

How to solve Nature and Essentials of a Valid Contract questions

Use this method for definition questions, essentials questions and fact-based problems.

1Define the key terms first: proposal, promise, agreement and contract, quoting Section 2 in your own words.
2State the relationship: contract = agreement + enforceability by law.
3List the essentials in a clear order: offer and acceptance, intention, consideration, capacity, free consent, lawful object, certainty, possibility, legal formalities.
4Give one line of explanation or one short illustration for each essential. Cite a section only where you are sure of it.
5For a fact-based problem, test the facts against each essential one by one and identify which essential is missing or defective.
6Name the legal result: valid contract, void agreement or voidable contract, with the reason.
7If money or goods changed hands under a void agreement, add that Section 65 requires the advantage to be restored or compensated.
8End with a one-line conclusion that answers the question asked.

Quickest way: Checklist for valid, void or voidable

When to use it: Use it for MCQs and short fact-based questions where you have under two minutes.

Ask: is there an agreement at all (proposal accepted)? If not, there is no contract.
Ask: is there consideration, or does a Section 25 exception apply? If not, void.
Ask: is the object lawful, the meaning certain and the act possible? If not, void.
Ask: was consent free and are the parties competent? Defective consent usually makes it voidable; a lack of competence needs a closer look at the facts.
If all pass, answer valid contract. Mention Section 65 if benefits were already received under a void agreement.

Common mistakes in Nature and Essentials of a Valid Contract

Saying every agreement is a contract.
The two words sound like synonyms in daily use.
Fix: Write the formula: contract = agreement + enforceability by law. Give a social agreement as the example of an agreement that is not a contract.
Treating a void agreement and a voidable contract as the same.
Both end in the contract not being fully enforced.
Fix: A void agreement is not enforceable by law at all (Section 2(g)). A voidable contract is enforceable until the entitled party chooses to avoid it (Section 2(i)).
Saying inadequate consideration makes an agreement void.
Students confuse inadequate with no consideration.
Fix: Section 25, Explanation 2 says inadequacy alone does not make an agreement void if consent was freely given. The Court may consider it when judging whether consent was free.
Treating a mistaken opinion about value as a mistake of fact.
Both feel like a mistake to the student.
Fix: Section 20 voids an agreement only where both parties are mistaken about a fact essential to it. The Explanation says an erroneous opinion as to value is not a mistake of fact.
Forgetting Section 65 when money was paid under a void agreement.
Students stop at the word void.
Fix: Add that a person who has received an advantage under a void agreement, or a contract that becomes void, must restore it or compensate for it.
Listing essentials with no explanation.
Students memorise only a list.
Fix: Give one line of meaning or one example per essential. Step marks come from the explanation, not the list.

Worked examples

Example 1

Distinguish between an agreement and a contract. Is every agreement a contract? (Short answer)

Show the solution

Agreement: under Section 2(e), every promise and every set of promises forming the consideration for each other is an agreement.
Contract: under Section 2(h), an agreement enforceable by law is a contract.
Difference in scope: agreement is the wider term; contract is the narrower one, as it needs legal enforceability.
Difference in effect: an agreement may not create legal rights; a contract creates legal rights and duties that a court can enforce.
Conclusion: all contracts are agreements, but not all agreements are contracts. Under Section 2(g), an agreement not enforceable by law is void.

Answer: Not every agreement is a contract. A contract is an agreement enforceable by law (Section 2(h)); an agreement that is not enforceable is void (Section 2(g)).

Example 2

Asha agrees to sell Bharat 'a hundred tons of oil' for ₹40,00,000. Nothing shows what kind of oil is meant, and Asha deals in several kinds. Bharat has paid ₹5,00,000 as advance. Is the agreement enforceable? What about the advance?

Show the solution

Identify the issue: whether the meaning of the agreement is certain. This is covered by Section 29.
Apply Section 29: agreements whose meaning is not certain, or capable of being made certain, are void.
Check for anything that can make the meaning certain, such as a specified description or Asha's trade. The facts give none, and Asha deals in several kinds of oil. The Section 29 illustrations treat this situation as void for uncertainty.
Conclude: the agreement is void and not enforceable.
Apply Section 65: Asha received an advantage under a void agreement, so she must restore it or compensate for it.

Answer: The agreement is void for uncertainty under Section 29. Asha must return the ₹5,00,000 advance to Bharat under Section 65.

Exam tips

In the MCQ section, test one essential at a time. The usual traps are void versus voidable, and no consideration versus inadequate consideration.
In written answers, open with the Section 2 definitions. Quote the idea, not the whole section, to save time.
For an essentials question, use a numbered list with a one-line explanation each. Aim for clear, short points.
For a problem question, always end with the legal status (valid, void or voidable) and, if money moved, the Section 65 consequence.
Learn the Section 1 facts: the short title, extent to the whole of India, and commencement on 1 September 1872. They come up as short MCQs.

Practice questions from Indian Contracts Act, 1872

Nature and Essentials of a Valid Contract in other exams

The same ground in other exams, if you are preparing for more than one or want another angle on it.

Nature and Essentials of a Valid Contract: frequently asked questions

What are the essentials of a valid contract?

The agreement needs a proposal and acceptance, consideration, competent parties, free consent, a lawful object, and meaning that is certain. It must not be declared void by the Act, and any legal formalities must be met. Explain each essential in a line in the exam.

What is the difference between a void agreement and a voidable contract?

A void agreement is not enforceable by law (Section 2(g)). A voidable contract is enforceable at the option of one party but not the other (Section 2(i)). It stays valid until the entitled party avoids it.

When does the Indian Contract Act, 1872 come into force and where does it extend?

Section 1 says it extends to the whole of India and came into force on the first day of September, 1872. It also saves usage or custom of trade and incidents of a contract that are not inconsistent with the Act.

Is a contract without consideration valid?

Generally no. Under Section 25, an agreement without consideration is void. The exceptions are a written and registered agreement made out of natural love and affection between near relations, a promise to compensate for something already voluntarily done, and a written, signed promise to pay a time-barred debt.