# Electronic shelf labels for warehouses and logistics

> What e-paper labels do in a warehouse: bin locations, pick-to-light, kanban and cold stores. What each KPI measures and what the sources actually say.

Source: https://etiquetaselectronicas.io/en/sectors/warehouses-logistics/
Published: 2026-11-09 | Updated: 2026-11-09

A warehouse electronic label is an e-paper display on a rack, bin or pallet position that shows what belongs there and, sometimes, how many to pick. It carries no price: a picker reads it from half a metre away, and its value is measured in lines picked per hour and errors per thousand.

That difference from retail changes almost everything. In a shop, the argument is how quickly a price reaches the shelf. In a warehouse the system already knows where everything is; what goes wrong is that the person walking the aisle has to see it in time and get it right. This page covers what these labels are used for, what the sources say about results, where the limits are and what tends to go unnoticed in a project.

## What the label does in each warehouse zone

Uses vary by zone, and not every zone justifies the investment.

| Zone | What the label shows | Why it pays off (or not) |
|---|---|---|
| Order picking | Item, location, quantity, sometimes an LED | This is where labour cost and errors concentrate |
| Racking with dynamic locations | Current location code and item | Reassigned without printing or swapping paper |
| Production line or replenishment (kanban) | Item, replenishment quantity, card status | Replaces the physical card that gets lost or goes stale |
| Chilled or frozen store | The same data, on a cold-rated model | Paper and ink degrade with condensation |
| High-bay reserve | Rarely labelled | Changes little; a printed code is enough |
| Receiving and dispatch docks | Destination, dock door, order | Useful if dock allocation changes daily; thinly covered in the sources |

### Bin location labels

The location label replaces the printed sign with a barcode and a slot name. The benefit is change without paper. If a location moves from small parts to large cartons, or is reassigned for a new season, the text and code update from the warehouse management system (WMS). SoluM, which makes labels for this use, describes segment-shaped formats designed for shelves and bins, and models with a built-in LED so staff can find an item.

The risk is the mirror image: a label that updates itself can also show the wrong data if the WMS changed the assignment and the update never arrived. Acceptance tests for a project should therefore measure how many labels in a sample match the system at any given moment, not just that the screen changes.

### Pick-to-light with a label

Pick-to-light has been in warehouses for decades: an indicator light at each location, a controller and a button to confirm. The electronic-label variant adds a display. The flow SoluM describes on its "digital picking" page has four steps: the system lights the LED at the next location, the operator checks quantity, code and variant notes on the label, presses the confirm button, and the system logs the time and user and moves on to the next task. SoluM proposes it for batch picking of several orders, for assembly lines and for e-commerce packing stations.

That same page gives no accuracy or productivity figures, and it is worth remembering when reading brochures: the flow is plausible, but the improvement is not measured in the manufacturer's own source.

### Kanban

A paper kanban system works as long as the card travels with the container. With an e-paper label on the container or on the replenishment shelf, the "card" updates by radio, with nothing to reprint or reposition. The sources we consulted mention it as a use, but we found no measured, published cases; this is the area with more marketing material than data.

### Cold stores

This is where an e-paper label has its clearest advantage over paper: printed paper wrinkles and ink runs with condensation. SoluM states that ordinary paper labels are unsuitable for sub-zero storage. But the technology has its own limit, and panel datasheets show how widely the range varies:

- A 2.9-inch Good Display panel is rated for operation from -25 to 40 °C and storage from -25 to 60 °C, although the manufacturer marks it as being phased out.
- A 13.3-inch industrial Advantech panel is rated for operation from -15 to 65 °C, and warns that after exposure to temperatures between 0 and -25 °C the panel must be left at room temperature for several days before mounting.
- Standard panels in many retail labels are rated 0 to 40 or 50 °C.

The panel is not the whole label. The battery, antenna, housing and the condensation that forms when moving from the cold room to the dock are separate factors, and panel datasheets say nothing about battery life in the cold. For a freezer, ask the supplier for the rating of the complete label, its runtime at that temperature and its moisture protection, then test a few dozen in the real cold room for weeks, including in-and-out cycles. [Our note on e-paper labels and cold](https://etiquetaselectronicas.io/en/technology/electronic-shelf-labels-freezers-chilled/) and the one on [battery life](https://etiquetaselectronicas.io/en/technology/electronic-shelf-label-battery-life/) go into those factors.

## What the KPIs measure and what the sources say

Two indicators account for most of the conversation.

**Lines picked per hour** (pick rate). A line is one SKU requested on an order, regardless of units. It is a labour productivity measure and depends heavily on order profile, travel distance and warehouse layout; comparing warehouses without normalising tells you nothing.

**Error rate.** Defects divided by total lines or items, depending on how each report defines it. Because every source picks its own definition, the figures cannot be added or averaged.

What we were able to verify:

- **Picking's share of cost.** The 2007 review by De Koster, Le-Duc and Roodbergen in the European Journal of Operational Research estimates that order picking can account for up to 55% of a warehouse's total operating cost and calls it the most labour-intensive activity. It is the authors' estimate and nearly twenty years old; it tells you where to look, not what to budget.
- **One pick-to-light case.** A 2012 case published by MHI, from the integrator Lightning Pick Technologies, describes a fashion accessories distributor that moved from paper-label picking to a light-directed installation connected to its WMS. They report order error rates improving from 0.32% to 0.0013% and lines per hour rising from 171 to 350 (105% more). Read it with care: it is told by the vendor, it is a single customer, and it is an installation of light modules on flow racks, not of electronic labels.
- **A vendor guide.** Boxic24's guide puts the pick-by-light error rate below 0.4% and that of paper lists between 0.5% and 2%. It does not explain how those figures were measured.
- **A survey cited by a vendor.** Raymond West cites a 2012 survey of 250 distribution centres in North America and Europe, with an average cost of $22 per picking error. It does not identify who ran the survey, so the figure stays an indication.

We found no independent study that measures lines per hour and errors in the same warehouse, under the same conditions, before and after installing electronic labels with LEDs. That is the honest conclusion: the figures in circulation come from vendors and integrators, and the most quoted ones are for classic pick-to-light.

## Integration with the warehouse system

The label knows nothing by itself. It receives from the WMS what to show and which location it belongs to, and returns the button confirmation. Conceptually, there are three things to decide:

1. **Who is in charge.** Either the WMS commands the label directly (the usual model) or middleware translates between the WMS and the label network.
2. **How each label is identified.** The label's physical ID has to be paired with the location code. This pairing is the heaviest job in commissioning: done by hand, thousands of locations mean days of scanning.
3. **What happens if the radio fails.** Metal racking and narrow aisles affect coverage. You need to plan where access points go and what the label does when offline; [gateways and coverage](https://etiquetaselectronicas.io/en/technology/esl-gateway-how-many-needed/) explains the general problem.

In practice the link is built one of two ways: scheduled file exchange, which is simple but leaves a lag between what the WMS knows and what the shelf shows, or a real-time interface, which you need if the button press has to confirm the line on the spot. For pick-to-light, files are not enough. Ask the vendor which WMS it has already connected in production, not which ones it "supports".

## Which regulation applies

No price-display rule affects a location label, because there is no consumer and no price. That makes buying simpler than for a [DIY store](https://etiquetaselectronicas.io/en/sectors/diy-hardware-stores/) or a supermarket. What does apply is the rule for the equipment itself: labels that transmit by radio fall under the Radio Equipment Directive 2014/53/EU in the EU and, in Great Britain, the Radio Equipment Regulations 2017. The sensible step is to ask the supplier for the declaration of conformity for the specific model. For cold stores and hazardous atmospheres there will be installation requirements specific to the site that depend on the type of installation and that we have not verified here; whoever designs the warehouse defines them.

## What it costs

None of the vendors we consulted publishes a per-label price for warehouse use, and marketplace prices are no guide. For a budget, the useful part is the variables:

- **Number of labelled locations**, not SKUs. Reserve and high-bay positions are usually left out.
- **Label size and type.** With an LED and a button it costs more than without.
- **Temperature range.** A freezer-rated model is a different product category.
- **Brackets and fixings** for the type of racking, which get forgotten when budgeting.
- **Radio infrastructure** and the effort of the initial pairing.

For the general cost and payback method, see the [price and TCO guide](https://etiquetaselectronicas.io/en/pricing/); manufacturers that declare logistics use are compared in the [vendor comparison](https://etiquetaselectronicas.io/en/comparisons/esl-manufacturers-compared/). If you are just starting, [what is an electronic shelf label](https://etiquetaselectronicas.io/en/guide/electronic-shelf-labels-how-they-work/) gives the basics.

## Where to start

A sensible warehouse pilot is not the whole warehouse. It is one picking zone with high location turnover, measured before and after with the same definitions of line and error, plus one cold aisle if you have one, over a couple of months. The most useful output of that pilot is three numbers: labels that do not match the WMS, picking errors per thousand lines, and real battery life in each zone.

## Frequently asked questions

### Does an electronic label replace the barcode on a bin location?

Not entirely. The barcode is still how a location is identified when scanned, and an e-paper label can display that same code on screen. What the label adds is that the content changes without printing: when a location is reassigned to another item, the code and the text update from the system. Before removing paper, check that the scanners already in use read a code on an e-paper display reliably at the resolution of the chosen model.

### What is the difference between classic pick-to-light and pick-to-light with an electronic label?

The classic version puts a module with an indicator light, a numeric display and a confirm button at each location, wired to a controller. The electronic-label variant adds an e-paper display to the LED that can show the item, the variant and the quantity, and it communicates by radio. Vendors present it as more flexible when the range or the locations change often; the wired module is defended on stability and response speed for fixed, high-turnover locations. The sources we consulted offer no independent comparison of the two.

### Do e-paper labels work inside a freezer?

It depends on the specific model. Standard displays are rated 0 to 40 or 50 °C; there are dedicated panels rated down to -25 °C, and label makers advertise freezer versions. What datasheets almost never state is battery life at that temperature, so ask the supplier and test in the real cold room before ordering in volume.

### How many labels does a warehouse need?

You count physical locations, not SKUs. A warehouse with 8,000 pick locations needs roughly 8,000 labels, plus any reserve or receiving locations you decide to label. High-bay pallet positions are usually left with a printed code because nobody sees them up close and they rarely change, which is why many projects label only the order-picking zone.

### Do price-display rules affect warehouse labels?

No. Rules on price indication, such as unit pricing or the 30-day reference price under the EU Omnibus Directive, apply to sales to consumers, and a location label shows no price. What does apply is equipment regulation: the Radio Equipment Directive 2014/53/EU in the EU, or the Radio Equipment Regulations 2017 in Great Britain, for devices that transmit by radio.

## Sources

- [De Koster, Le-Duc and Roodbergen (2007), Design and control of warehouse order picking: a literature review, European Journal of Operational Research 182(2)](https://pure.eur.nl/ws/portalfiles/portal/46713708/DesignandControl_2007.pdf)
- [Fashion Accessories Retailer Reduces Shortage Allowances Through Using Pick to Light Solution (Lightning Pick Technologies case, MHI, 2012)](https://og.mhi.org/downloads/industrygroups/solutions-community/casestudies/retail---pick-to-light.pdf)
- [Pick by light guide, Boxic24](https://boxic24.com/english/ratgeber/pick-by-light-guide)
- [Mispick Elimination, Raymond West](https://www.raymondwest.com/learn/blog/2020/apr/mispick-elimination)
- [Digital picking, SoluM](https://www.solum-group.com/esl-n-iot/industrial-solution/digital-picking)
- [How to select the right ESL for a warehouse, SoluM](https://solumesl.com/en/insights/select-right-esl-for-warehouse)
- [GDEH029D57LT e-paper panel datasheet, Good Display](https://www.good-display.com/product/212.html)
- [EPD-130B1 datasheet, Advantech](https://advdownload.advantech.com/productfile/PIS/EPD-130M/file/EPD-130B1_DS(050726)20260507172318.pdf)
- [Radio Equipment Directive 2014/53/EU, EUR-Lex](https://eur-lex.europa.eu/eli/dir/2014/53/oj)
- [The Radio Equipment Regulations 2017 (SI 2017/1206), legislation.gov.uk](https://www.legislation.gov.uk/uksi/2017/1206/contents)