Una compañía de garantía es típicamente una empresa que promete asegurar o proteger el valor de las transacciones ofrecidas por otra compañía que no genera ganancias.

Una garantía es una garantía, por una parte, del cumplimiento de un contrato celebrado por una segunda parte. Esto puede existir si el contrato es para bienes físicos o servicios intangibles recibidos por esa segunda parte. Una compañía de garantía es típicamente una empresa que promete asegurar o proteger el valor de las transacciones ofrecidas por otra compañía que no genera ganancias. Los miembros de la compañía de garantía actúan como garantes del negocio y contribuyen con una tarifa nominal para asegurarlo.

Las compañías de garantía se utilizan comúnmente en el Reino Unido (UK) para organizaciones sin fines de lucro que necesitan personalidad jurídica. También son favorecidos por clubes deportivos, sindicatos de afiliados, cooperativas de trabajadores y otras organizaciones sociales. En esa parte del mundo, una empresa de garantía debe incluir la palabra limitada en su título y no puede distribuir beneficios a sus miembros. Tampoco pueden dividir las empresas en acciones y distribuirlas entre los miembros. Tal actividad se consideraría capital social y viola las disposiciones para las compañías de garantía establecidas en la Ley de Compañías del Reino Unido de 2006.

Multiple types of guarantees exist, within the business world, that protect individuals and companies from financial downfall should a business transaction fail. These guarantees may be divided into two categories — guarantees that protect buyers and sellers, or guarantees that protect lenders and borrowers. Both serve to secure any claims lodged by one party against another for a variety of reasons related to a business transaction between them.

Guarantees that protect buyers and sellers include: bid bonds, advance payment guarantees, performance bonds, guarantee for warranty obligations, payment guarantees, and indemnity for a missing bill of lading. Bid bonds are typically used in international exporting and are used to protect the value of a product or contract. Advance payment guarantees are generally used in both international exporting and domestic trade to guarantee delivery of service or product to a buyer who has paid for the goods in advance of shipment. A performance bond, used nationally and internationally, secures any claims made by the buyer against the seller for lack of delivery of goods or services.

Warranty obligations protect against defects in the goods or services being traded. A payment guarantee typically protects the seller, should the buyer choose not to pay for goods and services. An indemnity for a missing bill of lading is used to protect sellers and shippers when goods are being transported and the bill of lading, the list of items in the shipment, does not arrive with the shipment itself.

Guarantees that protect lenders and borrowers usually center on securing a credit line. A guarantee to do this protects credit lenders, in case a borrower is unable to repay a debt. This type typically insures the amount of the loan as well as a small margin to account for interest on the original loan.

In China, the purpose of a guaranty company more closely resembles the creditor-borrower type. The China Banking Regulatory Commission created the Tentative Measures for the Administration of Financial Guarantee Companies to regulate these types of companies. The Tentative Measures describes a guarantee company as one that seeks to financially secure loans and other types of monetary financing provided by economic institutions, such as banks, to their customers. Unlike UK businesses, Chinese guarantee companies may have shareholders who are typically required to make regular monetary investments into the company, and may receive profits from it.