The person or entity that borrows money. The term debtor may be used interchangeably with the term borrower.

A debtor is an entity that owes a debt to someone else. The entity may be an individual, a firm, a government, a company or other legal person. The counterparty is called a creditor. When the counterparts of this debt arrangement is a bank, the debtor is more often referred to as a borrower.

Default occurs when the debtor has not met its legal obligations according to the debt contract, e. g. - it has not made a scheduled payment, or has violated a covenant in the debt contract. Default may occur if the debtor is either unwilling or unable to pay its debt. This can occur with all debt obligations including bonds, mortgages, loans, and promissory notes.

If the debt owed becomes beyond the possibility of repayment, the debtor faces insolvency or bankruptcy; in the United Kingdom and some states of the United States until the mid-19th century, debtors could be imprisoned in debtor's prisons, while in some countries such as Greece the practice of imprisoning debtors is still practiced. An Individual Voluntary Arrangement is a legally binding arrangement supervised by a licensed Insolvency Practitioner, the purpose of which is to enable an individual, sole trader or Partner ("the Debtor") to reach a compromise with his creditors and avoid the consequences of bankruptcy. The compromise should offer a larger repayment towards the creditor's debt than could otherwise be expected were the Debtor to be made bankrupt.

This is often facilitated by the Debtor making contributions to the arrangement from his income over a designated period or from a third party contribution or other source that would not ordinarily be available to a Trustee.