For one company, a serial number is overkill. For another, it's the only way to regain control over warranties and RMAs. The line between those two worlds doesn't run where most SMEs assume it does.
A typical call we get starts like this: "We have a disputed claim. The customer says the device was damaged on delivery. Third hour of talks, nobody knows which specific unit it is — our ERP only holds quantities, not individual pieces. We've lost the case both with the customer and the supplier, because we couldn't prove when that exact unit arrived." Then comes the question: "The ERP can do this, right? We just need to switch it on?"
The ERP can. But switching serialization on for the whole product range is, for most SMEs, a route to a daily annoyance that gives the company nothing. Deciding to serialize is an economic decision, not a technical one.
When serialization actually pays off
Serialization pays off when the cost of adding a serial-number scan at goods-in and goods-out is lower than the real risk of a dispute you can't resolve without one. In practice, that boils down to a few situations:
- High unit value. Above roughly 1 000–2 000 PLN net per piece, every return and every warranty claim hurts enough that it's worth knowing which exact unit came back.
- Individual warranty longer than 12 months. If a year later you have to prove to the supplier that a device is yours and still under warranty — without a serial number, you won't.
- Traceability required by law or standard. Calibrated measurement electronics, medical equipment, sporting firearms, some categories of power tools, components for the automotive industry — serial numbers have to be tracked there anyway.
- RMA to a foreign supplier. A German or Italian manufacturer will not accept a return without an SN. If you resell their products, their SN has to live in your ERP — otherwise the loss stays with you.
- In-house or authorized service. If a device comes back to you for repair, the serial number is the only way to know, two years later, what was done to it before.
In one project we rolled out serial tracking at a 22-person distributor of measurement equipment (multimeters, cable locators, calibrators) running on Microsoft Dynamics AX. Around 1 200 SKUs in total, of which 150 categories really needed per-unit tracking. Before the rollout: identifying a returned unit took on average 25 minutes (manual digging through delivery notes, matching dates with inbound shipments), and 3–4 disputes a month with foreign manufacturers over which specific unit was defective. After the rollout: 2 minutes to identify, one dispute per quarter, because the manufacturer no longer has anything to push back on. Time saved on warranty handling across the warehouse and sales desk — about 12 hours a week. Reduction in losses on lost warranty cases with suppliers — the client estimated it at about 25 000 PLN per year.
Notice that none of these benefits come from the "modernity of the system". They all come from one thing: when a claim arrives, you know which exact unit came back, when it arrived, and what was done to it before.
Where serialization doesn't pay off
That same distributor also stocks cables, connectors, batteries and accessories priced at 10–40 PLN. Turning serialization on for that part of the catalogue would cost the warehouse operator an extra 2–3 hours a day of scanning and opening master cartons to pull individual SNs. Benefit: zero. No individual warranty, claims settled by batch quantity, no SN required for RMA by the supplier.
A few typical traps that companies fall into after a first successful pilot in one category:
- "The ERP has that checkbox, so let's switch it on everywhere." A single scan adds 5–15 seconds to every warehouse operation. Multiplied by thousands of units a day, that's real labour time nobody factored into the business case.
- Serializing items that nobody returns anyway. If a given category doesn't generate claims or warranty disputes, SNs only slow the warehouse down.
- Manual SN entry without a scanner. That's not serialization, that's a typo generator. If there's no budget for barcode scanners and warehouse terminals, don't start.
- Serialization during stocktake. The temptation is big: we have SNs, so let's count by unit. In practice, stocktake takes three times longer and the information value is zero. Most companies go back to quantity-based stocktake after a year, keeping SNs only for the claims flow.
How to start without a revolution
Serialization is not a module deployment, it's a change in how the warehouse and the aftersales desk work. Start as narrow as you can.
- Pick one or two categories that generate 80% of your warranty disputes. Count how many times in the last 12 months you lost a claim or an RMA because you couldn't identify the unit. That's your real benefit.
- Enable SNs at goods-in and goods-out only — not in stocktake, not in internal production, not in internal returns.
- Give the warehouse operator a scanner. Any manual SN input will eventually break. A cheap 70-euro scanner beats correct paper procedures.
- Keep the map: SN → supplier → delivery date → supplier invoice. Without that link, serialization gives you nothing more than a sticker in the ERP.
- Measure: disputes before and after. If after six months the number of disputes hasn't dropped visibly, you're serializing the wrong category. Don't be afraid to roll it back.
- Don't serialize "just in case". Every SN you add "to be safe" costs warehouse time every day, and its value only shows up in rare cases. The maths doesn't work out.
Most SMEs we talk to settle, after about a year, into a stable state: serialization run consistently for 5–15% of the catalogue, that part generates 70–90% of claim value, the rest flows without SNs and nobody misses them. It's not a compromise — it's a correctly chosen scope.
If you're thinking about turning on serial numbers in your ERP and don't know which category to start with or how to work out whether it's worth it — rather than buying the module and trying, talk to someone who has run these rollouts in several companies. The first call is free and takes half an hour.
Serialization is an economic decision, not a technical one. The ERP almost always supports it — the question is whether your company gains more than the warehouse loses in the seconds added to every operation.