A complimentary slip, also known as a compliment slip or compliments slip, is a small slip of paper typically included with a package, letter, or document to convey a polite message. It usually contains a brief message expressing gratitude, appreciation, or goodwill. Complimentary slips are commonly used in business settings to accompany delivered goods, documents, or as a way to acknowledge a favor or gesture. They often feature the company logo, contact information, and a blank space for a personalized note.