Electronic shelf label accessibility: what can be read, what cannot, and what the law says

An electronic shelf label is accessible when a shopper with low vision, colour blindness or blindness can find out what a product costs without asking for help. That depends less on the display than on the template: price size, contrast, a second cue besides red and, for people who cannot see, NFC linked to a screen-reader-friendly page.

A problem paper already had

Start here, because it is easy to overcorrect. Paper shelf-edge labels also carry tiny prices, fading ink and red-on-yellow promotion tags. Nobody audits them. An electronic label forces you to decide the template once and apply it to thousands of shelves, which is a risk (a mistake is made everywhere) and an opportunity (a good choice is made everywhere).

For the general technical picture, see the guide to electronic shelf label technology. Here we stay with what matters to the person reading the label.

Legibility: size, contrast and distance

Size. We have not found any rule that sets a minimum type size for the price on a shelf label. What the law does require is a matter of principle. Spain’s Royal Decree 3423/2000, article 4.1.a), says the selling price and the unit price must be “unambiguous, easily identifiable and clearly legible” (our translation) and placed in the same field of view. It transposes the EU price-indication directive, so equivalent wording should exist in your national law; check the text for your country. “Clearly legible” is not defined in numbers, and it is the test an inspector would apply.

Clear-print guidelines for people with low vision do give figures: most ask for 12 point as a minimum and 14 point as recommended (the Sensory Trust factsheet is one example). Those are made for paper held at 30 to 40 centimetres. In a low aisle bay the shopper is standing and the label may be a metre or more away. So the practical rule is to test: print the template at real size, hang it on the lowest and the highest shelf of the aisle and ask someone to read the price from where people normally stand. If they must crouch or lean in until they almost touch it, the price is too small.

A common mistake is giving the unit price the same weight as the selling price. Shoppers look for the second; the first is required by law and often ends up tiny. With a small display you must decide what to sacrifice, and the right answer is usually the long product name, not the price.

Contrast. WCAG 2.2 asks for a contrast ratio of 4.5:1 for normal text and 3:1 for large text (18 point, or 14 point bold). It is a standard for web content, not a labelling rule, but it is the reference most used and can be measured on a screenshot of the template. Black on white clears it easily on any e-paper panel. The trouble starts with colour: red on white, or soft grey lettering chosen “so as not to distract”, can fall short. Measure before approving a template instead of trusting your eye.

Brightness and glare. E-paper reflects ambient light instead of emitting it, so it does not dazzle like a backlit screen and stays readable in strong light. That does not make it glare-free: a glossy plastic cover or a lighting strip right above the shelf can throw a flash that hides the price. The test is the same, on site and at different times of day. If you are comparing technologies, LCD versus e-paper contrast is covered separately.

Older shoppers: what changes in practice

Presbyopia and reduced contrast sensitivity mean small grey prices are the first to become unreadable. There is also a less obvious effect with electronic labels: change. Someone used to a price that stays put for weeks trusts it. If the label updates while they read it, or shows a second price now and then, they may doubt what they saw. Avoid displays that alternate content (price, unit price, QR code) on one label and keep one stable face.

Height matters too. Bottom-shelf labels are the worst for anyone who finds it hard to bend down; if the store already knows a range is a regular purchase for older customers, raising it is cheaper than any technology. Opticians have an obvious connection to this topic; see the optical retail sector.

Colour blindness and red on promotions

According to Colour Blind Awareness, colour blindness affects one in 12 men (8 %) and one in 200 women, and red-green confusion is the most common; very dark reds, greens and blues can also be mistaken for black.

Three-colour labels (black, white and red, the BWR family E Ink presents as Spectra 3000) make red the promotion colour. If the only sign of a markdown is a red price, part of the shoppers, mostly men, cannot tell that signal from black. Better to rely on several cues:

• the previous price struck through next to the new one,
• a word or symbol (“Sale”, “−20 %”) in black,
• a box or an inverted block (white text on black or dark red) instead of a hue change alone,
• red-on-background contrast of at least 3:1 or 4.5:1 depending on size, as for black.

That turns red into reinforcement for people who see colour rather than the only information. Multi-colour variants (BWRY, six colours) add more confusable combinations, not fewer; the article on colour labels covers what each step costs and when it is justified. For accessibility, the answer is almost always the plainer one.

Does the European Accessibility Act apply to a price label?

The question comes up more and more, and the honest answer is “probably not by itself, but we do not treat it as closed”.

Directive (EU) 2019/882, the European Accessibility Act, applies in member states from 28 June 2025. The European Commission summarises the products and services covered: computers and operating systems, ATMs, ticketing and check-in machines, smartphones, digital TV equipment, telephony services, audiovisual media services, passenger transport, banking services, e-books and e-commerce. National law adds detail; in Spain it is Law 11/2023, and the Spanish version also names certain self-service terminals, such as payment terminals, as Cuatrecasas notes.

A shelf label is not on those lists, and it is not a terminal where the person enters data or pays. Where contact with the law is possible is around the store:

Micro-enterprises cause a lot of confusion, so it is worth going to the text. Spain’s Law 11/2023, following the directive, defines a micro-enterprise as one with fewer than 10 staff and no more than 2 million euro in annual turnover or balance sheet, and exempts micro-enterprises that provide services from the accessibility requirements for those services. Products get no such exemption, only lighter paperwork. For a small store that usually concerns its online shop, not its shelf labels, which were out of scope anyway. How your own case fits is still a question for a lawyer in your country.

Blind shoppers: NFC and voice, realistically

An NFC label lets a phone read a link when held against it (range of a few centimetres). A blind person using the phone’s screen reader can, in principle, tap the label and hear the name, the price and the unit price. Three conditions are often forgotten:

1. The destination page must be accessible, with real text, not an image of the price.
2. The person must be able to find the label. Without a tactile mark or a fixed position on the shelf, tapping “where you think it is” does not work.
3. The data must match the shelf. It is one more place for discrepancies, on top of the till price differing from the shelf.

This route depends more on the retailer than on the label maker. And it is optional: we have found no rule that demands it.

What to ask for at purchase and in the pilot

To avoid relying on promises, three concrete checks that fit in a pilot project:

• Ask the vendor for a contrast report of the panel and of red under store lighting, and verify it with a light meter and a camera.
• Test the template with low-vision and colour-blind people from your staff or customers, without telling them what is being measured.
• Add an accessibility row to the vendor checklist: editable templates, configurable minimum price size, and NFC or QR with a destination you control.

What we do not know

We have found no public, comparable measurements of contrast and reflectance of red on ESL panels from different manufacturers; E Ink’s public sheet for Spectra 3000 gives no figures. Nor is there, as far as we know, a rule on type size for shelf labels in Spain. If either exists and you have seen it, write to us and we will correct this page.