Definition
Customer part number (CPN)The identifier a buying organisation gives an item in its own records. It belongs to the customer, not the item: the same bolt can carry a different customer part number at each customer that buys it. Also called customer item number, customer material number or customer product code.
Customer part number vs SKU vs manufacturer part number
| Number | Who assigns it | Where you meet it | Example |
|---|---|---|---|
| Customer part number | The customer | Their enquiries, purchase orders and drawings | 100-4471 |
| SKU (your product code) | You, the distributor | Your ERP, catalogue and price lists | 1293340 |
| Manufacturer part number (MPN) | The manufacturer | Packaging and datasheets | HB-M12-50-ZP |
| Competitor’s code | Another distributor or brand | Enquiries from customers who bought elsewhere | XB 931 1250 |
Codes invented for illustration. One item has one SKU but can have a different customer part number at each customer.
Why do customers use their own part numbers?
A manufacturer or contractor buys similar items from several suppliers, and its purchasing system needs one code per item, whichever supplier delivers it. That code survives a change of supplier and appears on the customer’s drawings and bills of materials. Its goods-in and accounts payable teams then match deliveries and invoices by that code, which is why many buyers want it on your order confirmation, delivery note and invoice.
Why are customer part numbers hard for distributors?
- Every customer has its own codes. The same item can have a different number at each customer, and the same number can mean different items at two customers.
- Not always one to one. A drawing number or kit code can stand for a fixed set of parts.
- Codes change. Customers sometimes renumber and your items get superseded, so an old pair can point to the wrong item.
- The cross-reference is scattered across a customer item table in the ERP, spreadsheets and reps’ memory, and new customers are rarely in any of them. Put a figure on that manual work with the quote cost calculator.
Example: a purchase order written in customer part numbers
A manufacturing customer emails a fastener distributor a purchase order printed from its own ERP.
Purchase order PO-58812 (PDF attachment)
- 100-4471 HEX BOLT M12X50 ZP, 200 EA
- 100-4472 HEX NUT M12 ZP, 200 EA
- 100-5208 FLAT WASHER M12 ZP, 400 EA
- KIT-220 GUARD FIXING KIT, 10 EA
- 300-1185 SEAL, 4 EA
| Customer part number | Proposed item | Match score | How |
|---|---|---|---|
| 100-4471 | 1293340 Hex bolt M12x50 8.8 zinc plated | 100 | Pair learned from lines your team sent |
| 100-4472 | 1293410 Hex nut M12 class 8 zinc plated | 100 | Learned pair; description agrees |
| 100-5208 | 1295020 Flat washer M12 zinc plated | 91 | Code not seen before: identified from description and size |
| KIT-220 | 40 × 1293340 hex bolt, 40 × 1293410 hex nut, 80 × 1295020 washer M12 (customer-code set) | 100 | Set you supplied for this customer: one code expands into its fixed lines |
| 300-1185 | Placeholder code | 0 | Unknown code, thin description: marked |
Illustrative example with invented codes, items and scores. The customer’s code stays next to each proposed item.
How does ERP Agent handle customer part numbers?
ERP Agent reads the enquiry or order from email, PDF, Excel or Word and identifies the right product in your catalogue for each line. For customer codes it uses pairs learned from your past quotes and the lines your team sends, so the next time a customer writes the same code, it picks the same product. Sales history, when provided, narrows the search to what that customer buys.
A code it has not seen before is identified from the rest of the line (description, sizes, material), and candidates that contradict a stated size are pushed down. A line it cannot identify from either goes on your placeholder code instead of a guess. Proposed codes are checked against your ERP before sending, so a pair pointing to a code that is no longer there is caught.
Every line carries a match score from 0 to 100, lines under 80 are marked, and by default a person approves before anything lands in your ERP, CRM or other system. More in customer part number cross-reference, AI quote automation and order entry automation.
