Section 133 explained: this guide covers what it means, who it applies to, the step-by-step process, documents required, fees, due dates and penalties in India — so you can stay compliant with confidence and avoid costly mistakes.
Section 133 protects a surety from a change he never agreed to. If the principal debtor and the creditor alter the terms of their contract without the surety's consent, the surety is discharged as to transactions after the change. If a guarantee dispute turns on such a change, our legal dispute resolution service can help you read the documents.
Any variance, made without the surety's consent, in the terms of the contract between the principal debtor and the creditor, discharges the surety as to transactions subsequent to the variance. The rule has two conditions: a variance in the terms, and no consent from the surety. The discharge looks forward: it covers transactions after the variance, not those before it.
The text
Section 133 reads: "Any variance, made without the surety's consent, in the terms of the contract between the principal debtor and the creditor, discharges the surety as to transactions subsequent to the variance."
The word "debtor" in the section was inserted by Act 24 of 1917, as the footnote to the section states. Principal debtor, creditor and surety are the terms defined in section 126; see section 126.
Limb by limb
| Limb | What it means in plain words |
|---|---|
| "Any variance" | Any change in the terms of the contract between the principal debtor and the creditor. The text does not say the change must be large or harmful. |
| "In the terms of the contract between the principal debtor and the creditor" | The change is to the main contract, not to the guarantee itself. |
| "Without the surety's consent" | If the surety agreed to the change, the section does not apply. |
| "Discharges the surety" | The surety's liability ends. |
| "As to transactions subsequent to the variance" | Only later transactions are affected; earlier ones are not mentioned as discharged. |
The section does not ask whether the variance helped or hurt the surety. Its test, on its words, is variance plus absence of consent.
The Act's illustrations
The Act gives five illustrations. In each the surety is discharged.
- Illustration (a). A becomes surety to C for B's conduct as a manager in C's bank. Later B and C agree, without A's consent, that B's salary will be raised and that B will be liable for one-fourth of losses on overdrafts. B allows a customer to overdraw and the bank loses money. A is discharged by the variance and is not liable for the loss.
- Illustration (b). A guarantees C against B's misconduct in an office to which C appoints B, the duties being defined by an Act of the Legislature. A later Act materially alters the nature of the office. B then misconducts himself. A is discharged by the change from future liability, even though the misconduct concerns a duty the later Act did not touch.
- Illustration (c). C agrees to appoint B as clerk to sell goods at a yearly salary, A becoming surety for B's duly accounting for money received. Without A's knowledge or consent, C and B agree that B will be paid by commission instead of a fixed salary. A is not liable for B's later misconduct.
- Illustration (d). A gives C a continuing guarantee up to 3,000 rupees for oil supplied by C to B on credit. B becomes embarrassed and, without A's knowledge, B and C agree that C will continue to supply oil for ready money, with the payments applied to existing debts. A is not liable for goods supplied after the new arrangement.
- Illustration (e). C contracts to lend B 5,000 rupees on 1 March and A guarantees repayment. C pays the 5,000 rupees on 1 January. A is discharged, because the contract was varied: C might sue B for the money before 1 March.
Illustration (e) is a reminder that even a change of timing counts as a variance.
A modern example of our own
Anil Traders has a credit limit with a wholesaler, and Neha has signed as surety for the dues. Later the wholesaler and Anil Traders agree to raise the credit period from 30 days to 90 days, and Neha is not told. Read with section 133, a change of this kind, made without her consent, discharges Neha as to transactions after the change. If Neha had agreed to the new credit period in writing, the section would not apply, because the variance would no longer be "without the surety's consent".
What can the parties change?
Section 133 does not contain the words "in the absence of any contract to the contrary". The consent of the surety is built into the rule itself: a variance with the surety's consent does not discharge him. Because the section speaks of consent, many guarantee deeds record the surety's advance agreement to future changes. Whether such a clause works as consent for a particular change depends on its wording, and the text of the section does not answer that; take advice on the specific deed.
What the section does not say
- It does not say the consent must be in writing. It says "without the surety's consent".
- It does not say what happens to transactions before the variance beyond limiting the discharge to later ones.
- It does not mention variance of the guarantee itself, only of the contract between the debtor and the creditor.
Practical points
- Creditors: if you plan to change repayment dates, interest, security, limits or duties, get the surety's consent first and keep it on record.
- Sureties: ask for copies of every amendment to the main contract and read them against your guarantee.
- Both sides: keep a dated list of changes so it is clear which transactions came before and which after.
- For the related rule on releasing the debtor, see section 134.
Need help with a guarantee dispute?
A claim on a guarantee often turns on whether the main contract was changed along the way. Our legal dispute resolution team can look at the original contract, the amendments and the correspondence, and tell you where each party stands under section 133. Bring every version of the agreement you can find.
Key takeaways
- A variance in the terms between the principal debtor and creditor, made without the surety's consent, discharges the surety (s.133).
- The discharge applies to transactions after the variance.
- The Act's five illustrations include a salary change, a change in the nature of an office, a change from salary to commission, a change from credit to cash, and an early payment of a loan.
- If the surety consents, the section does not discharge him.
Read next
- Section 134: discharge of surety by release or discharge of principal debtor
- Section 135: discharge of surety when creditor compounds or gives time
- Specimen deed of guarantee: bank and performance guarantee format
Disclaimer: Based on the text of the Indian Contract Act, 1872 as consulted on 1 October 2026. Many questions under this Act turn on case law and on the wording of the particular contract, which this article does not cover. It is general information, not legal advice; check the official text and take advice before acting.