I’ve recently received a question like this from a student: “What is better to use on a purchase order: an item number or a free text description?”
Well, first let me say that these two pieces of information do not need to be mutually exclusive.
The purpose of an item number, purchase order description, or specification is simple: to communicate to the supplier what you have ordered in a manner that makes it unlikely (ideally, impossible) for a supplier to misinterpret what it is that you want.
The amount of information required on a purchase order differs depending on what you’re buying. When an item number removes the probability of getting something that is different than what you wanted, then that is all you need. But for less common or less tangible purchases (especially services), you will need more descriptive text – maybe even a 40-page specification.
So, the only correct answer is “it depends.”
However, using supplier item numbers where they are available helps put the understandings between you and your supplier in harmony.
More of these types of purchasing basics are covered in our online purchasing course, “Mastering Purchasing Fundamentals.”