Which word should be used in place of 'guarantee' in a sales context?

In a sales context, the word "warranty" is most appropriate in place of "guarantee" because it specifically refers to a formal assurance that a product will perform as promised or that certain conditions will be met. A warranty typically includes details on what is covered, the duration of the coverage, and the process for making claims, making it a legal commitment from a seller to the buyer. This adds a layer of trust and accountability that is critical in sales, especially in industries such as home services, where customers seek assurance about the products and services they purchase.

While "assurance," "promise," and "certainty" convey positive connotations regarding reliability and trustworthiness, they do not carry the same formal implications as a warranty. "Assurance" can suggest confidence but lacks the contractual undertone of a warranty. "Promise" provides a sense of commitment, but it does not necessarily imply legal protection or recourse in the same way a warranty does. "Certainty" is more about confidence in outcomes rather than an explicit commitment about a product's performance. Therefore, "warranty" stands out as the most suitable substitute in a sales context.