Business-to-business (B2B or, in some countries, BtoB) is a situation where one business makes a commercial transaction with another.

This typically occurs when:

• A business is sourcing materials for their production process for output (e.g., a food manufacturer purchasing salt), i.e. providing raw material to the other company that will produce output.
• A business needs the services of another for operational reasons (e.g., a food manufacturer employing an accountancy firm to audit their finances).
• A business re-sells goods and services produced by others (e.g., a retailer buying the end product from the food manufacturer).