Warm calling is the solicitation of a potential customer with whom a sales representative or their firm has had some prior contact. It refers to a sales call, a visit or an email that's preceded by some sort of contact with the prospect, such as a direct mail campaign, an introduction at a business event, or a referral.

Warm calling is the opposite of cold calling, the solicitation of prospects who weren't anticipating such interaction and with whom the sales representative or business has not had prior contact.