Set-off (law)

In law, a set-off is an equitable defence to the whole or to a portion of a plaintiff's claim. A set-off is the right of a debtor to balance mutual debts with a creditor. In bookkeeping terms, set-offs are also known as reconciliations. To determine a set-off, simply subtract the smaller debt from the larger. Any balance remaining due either of the parties is still owed, but the remainder of the mutual debts has been set off.

The right to set off is particularly important when reporting a bank's exposures to regulatory authorities. The situation where a bank has to report that it has lent a large sum to a borrower (and is therefore exposed, because there is a risk that the borrower might default thereby leading to the loss of the bank's or its depositors' money) is thus replaced (where the bank has taken security over shares or securities of the borrower) with an exposure of the money lent minus the value of the security taken.

Under English law, there are broadly four types of set-off which have been recognised:

See De Magno v. United States, 636 F.2d 714, 727 (D.C. Cir. 1980) (district court had jurisdiction over claim involving VA’s “affirmative action against an individual whether by bringing an action to recover on an asserted claim or by proceeding on its common-law right of set-off”) (discussing similar language of predecessor statute, 38 U.S.C. § 211)

See, e.g., United States v. Munsey Trust Co., 332 U.S. 234, 239, 67 S.Ct. 1599, 1601, 91 L.Ed. 2022 (1947) ("government has the same right 'which belongs to every creditor, to apply the unappropriated moneys of his debtor, in his hands, in extinguishment of the debts due to him' " (quoting Gratiot v. United States, 40 U.S. (15 Pet.) 336, 370, 10 L.Ed. 759 (1841))); see also Tatelbaum v. United States, 10 Cl.Ct. 207, 210 (1986) (set-off right is inherent in the United States government and grounded on common law right of every creditor to set off debts).

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