Русско-англо-русский юридический словарь

Set off in its simplest form is generally understood by legal practitioners and laypersons alike - it refers to the reduction or extinguishment of a claim by a co-existing counter-claim. Thus, if Justinian owes £100 to Gaius and Gaius owes £80 to Justinian, set off can intervene to reduce the co-existing claims to a single claim for £20 owed by Justinian to Gaius. (Morton Fraser Lawyers)

Set-off, at its most basic, is a mechanism whereby one party can apply a debt owed to him or her by another party to discharge all or part of a debt that he or she owes to that other party. (Set-off - NSW Law Reform Commission)

If you want a noun referring specifically to reduction of the amount owed by debtor to creditor by some other amount that the creditor owes the debtor, use the noun setoff or set-off. While offset would not be a mistake setoff or set-off would be more precise. (the (new) legal writer)

Netting is similar to the concept of setoff, except that setoff is typically effected under a single agreement or transaction while netting occurs when parties to two or more agreements agree to aggregate payments across agreements in order to simplify and reduce payment obligations. (Practical Law)

Netting is the process contractually agreed by counterparties to consolidate mutual claims into a single net balance. This involves the termination of the mutual transactions, their valuation and the replacement of the liabilities for a single payment. (Trinity International LLP)