Supplier shipped too much: handling overdelivery without paying for it
A decision table and worked example for supplier overdelivery: verify the surplus, pick keep, return, or hold, and record it without paying unagreed.
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Short answer: count it, quarantine it, and get the supplier's instruction in writing before you pay for it or shelve it. Overdelivery — more units of the right SKU than you ordered — is the surplus twin of being short-shipped: the item is correct, the quantity isn't. What to do when the count comes up short instead is covered in our short-shipment guide; this piece handles the surplus side: a verify-first routine, the four dispositions, and a worked example with the arithmetic spelled out.
First, verify it's actually surplus
A supplier shipped extra units for reasons that are usually mundane, so confirm what happened before deciding anything:
- Recount. Count the actual units, not cartons. A "72" that's really 12 boxes of 6 is a different problem than 12 loose extra pairs.
- Compare three documents. Purchase order, packing slip, invoice. Surplus against the PO but matching a corrected packing slip usually means the supplier already decided something; surplus against all three means they haven't.
- Rule out the boring explanations. A second PO shipped early, or a backordered line from months ago arriving on top of a fresh order. Check your open orders before you call this an error — the fix differs completely. And if it's the same PO arriving twice, that's a full duplicate shipment rather than surplus: the duplicate delivery playbook is the incident guide for that.
- Rule out substitution. If the extra units are a different SKU than you ordered — even a "better" one — that's a wrong-goods incident, not a surplus. The claim process for that lives in our wrong-items walkthrough.
The four dispositions
Once it's genuinely surplus of the right item, every path is one of four moves:
| Your situation | Move | Paperwork that closes it |
|---|---|---|
| You'd reorder this item soon anyway | Keep it, request a corrected invoice | Corrected invoice received before you pay |
| You don't need the extra units | Offer to return them at the supplier's cost | Return authorization, freight answer in writing |
| Supplier tells you to keep them | Keep as agreed free goods | Written confirmation; record the units at zero cost |
| No answer after a reasonable time | Hold in quarantine, keep reminding | Dwell log entry plus dated follow-ups |
One legal anchor: under UCC Article 2, a tender of the wrong quantity gives a buyer grounds to reject all or part of the delivery (accessed November 2026). In practice that means the surplus isn't yours until it's agreed — "hold and ask" is the default, not a courtesy you're doing the supplier.
Worked example: 60 pairs ordered, 72 arrive
Illustrative numbers throughout — swap in your own costs and velocity. You ordered SOCK-MRN-L hiking socks: 60 pairs at a $7.80 unit cost, $468.00 total on the PO. The packing slip says 72. You count the box: 72. The invoice still says 60 pairs, $468.00.
The 12 extra pairs, at cost: 12 × $7.80 = $93.60 (illustrative). Three realistic paths:
- Keep all 72, corrected invoice. You'd owe $561.60 total. At an illustrative velocity of 2.5 pairs a day, 12 pairs is roughly five extra days of stock on an item you'd reorder soon — the cover arithmetic is in our days-of-cover guide. If those units were on next month's order anyway, this is usually the cleanest outcome: one corrected invoice, no freight, no dead time.
- Keep 60, return 12. Estimated return freight of $14 (illustrative) against $93.60 of cost value means spending about 15% of the surplus's value to recover the rest, plus the packing time. This makes sense when you genuinely can't sell the extra within a reasonable window, or when the supplier is overseas and return freight terms need checking against your agreed Incoterms 2020 term (International Chamber of Commerce, accessed November 2026).
- Keep 60, hold 12 pending instruction. Zero spend, zero risk. The 12 pairs sit in quarantine with a log entry until the supplier answers, then convert to whichever of the first two paths applies.
What not to do: pay the $468.00 invoice and shelve all 72 without a word to the supplier. Now stock on hand (72) disagrees with the books (60), a future count flags variance nobody can explain, and the supplier can bill the difference a year later with no paperwork on your side.
Suppliers usually respond to an overdelivery report well, for a plain reason: the error is theirs to find, and a merchant who documents it cleanly has done most of their reconciliation for them. The ask costs one email. The alternative — an invoice fight months later, or carrying 12 pairs that were never paid for — costs the relationship, the count accuracy, or both. Whichever path you pick, pick it in writing: a one-line reply confirming "we'll send a corrected invoice" or "keep them, consider it a sample" closes the incident in under a minute of their time and gives you the paper trail.
Recording the surplus without polluting your counts
- Receive the PO quantity into sellable stock. Book 60 pairs against the purchase order and pay against it; that keeps the PO-to-receipt trail clean (Shopify Help Center on receiving purchase orders, accessed November 2026).
- Quarantine the surplus physically. The extra 12 pairs stay in the hold zone, separate from sellable stock, until the answer arrives.
- Adjust only on written agreement. If the supplier confirms the units are free goods, record a +12 adjustment with a note referencing the email; if they want them back, the return happens from quarantine, never from the shelf.
- Expect the knock-on effect on reordering. Twelve extra pairs is about five days of cover at the illustrative velocity — your next order date slides out, and it's better to see that coming in the numbers than be surprised by a delayed PO.
- Recheck the next receipt from that supplier. Overdelivery is often a picking-line habit at their warehouse, not a one-off; the next delivery is where you find out whether it repeats.
Common questions
What is supplier overdelivery? It's when a supplier ships more units than you ordered of the same, correct item — you ordered 60 pairs and 72 arrived. It's the quantity-surplus case. Shortages are the mirror image, and wrong items are a different incident with different paperwork.
Do I have to pay for goods I didn't order? No. You didn't order them, and under UCC Article 2 a wrong-quantity tender gives you the right to reject them. The practical default: hold the surplus, tell the supplier promptly, and pay only against a corrected or confirmed document.
Can I keep and sell the extra units? Only once it's agreed. If the supplier confirms in writing that the extras are free goods, record them at zero cost and sell them normally. Until then, selling unagreed stock makes it look like you accepted a new contract at full price.
What if the invoice already includes the surplus? Check it against the PO before paying anything. If you're keeping the goods, a corrected invoice matching the received quantity is fine; if you're returning them, dispute the surplus line in the same message as your return request.
Should I automatically return overdelivered stock? No — compare the numbers first. Return freight, restocking fees, and handling can eat a meaningful share of the surplus's value, as the worked example shows. If you'd reorder the item soon, keeping it against a corrected invoice is often cheaper for both sides.
Next step
Pull your last three POs today and compare each invoice's quantities against what you actually received — resolve any mismatch now, while the paper trail is fresh, using the verify routine above. The ordering side that keeps quantities clean in the first place is covered in our purchase-order process guide.