When to trust out of home advertising reviews and when to verify instead

What to take away

Why out of home advertising reviews changed in the UK

The old review format asked whether a billboard looked good. The current format asks what data sits behind the panel, who controls it, and whether the site has planning consent for the format being sold.

Out of home advertising reviews used to be judged on visibility, location and price. Those still matter. What has changed is that a growing share of the inventory is digital, addressable or measured by device-level data, and that pulls the medium into rules written for online advertising.

The Online Safety Act 2023 extended duties to certain user-to-user and search services, and advertising carried on those services can be caught. For buyers, the practical effect is that a provider's data practices are now part of the review, not a footnote.

Separately, the Information Commissioner's Office has been issuing decision notices against organisations over advertising technology and data handling. Those notices are public, and they are the fastest way to check whether a measurement partner in your media plan has a regulatory history worth knowing about.

Planning law is the third strand. Advertisement control sits largely in the Town and Country Planning Act 1990, and the detail is in the Town and Country Planning (Control of Advertisements) (England) Regulations 2007. A site sold as having deemed consent may not have it.

None of this means out of home is riskier than other channels. It means the evidence you need before signing has changed, and a review that predates these shifts is not a review you can rely on.

What should a review check, and what evidence should you demand?

Start with the inventory, not the pitch. A supplier should be able to name the sites, the format, the illumination, the size and the contract length for each.

If you are comparing several suppliers at once, our guide to out of home advertising product comparison shows how to line up formats and rates so the numbers are genuinely comparable.

A real review contains at least one thing the supplier would rather you did not read. That is the simplest test.

Look for named sites. "Premium London locations" is not a site list. "Two 48-sheet panels on the A4 corridor, both illuminated, both with deemed consent" is.

Look for dates. Audience figures, traffic counts and availability change. A review with no date cannot be checked and should be treated as undated marketing.

Look for an admission of limits. Every provider has formats it does not sell well, regions it cannot cover, or minimum spends that rule out small campaigns. A review that finds no weaknesses has not looked.

Look for the source of any audience claim. If the number is footfall, say so. If it is modelled, say so. If it is a device-based estimate, say so and say who modelled it.

This is also where regulatory sources earn their place. The ASA news and updates on advertising regulation page is worth checking before you accept a supplier's assurance that a creative route is fine. Rulings on out of home and adjacent formats are published there, and they move the line.

The ASA ruled against a Floki Inu campaign on London buses in March 2022, which is one example of out of home creative being held to the CAP Code.

The site schedule should list every location, format and contract end date. A site that comes off contract in three months cannot support a twelve-month campaign. If the supplier cannot produce the schedule, the review stops there.

Our out of home advertising review methodology explains how we score those documents, including how we weight measurement quality against coverage and how we treat missing paperwork.

The measurement methodology should name the data source, the sample or panel, the modelling approach and the refresh frequency. A single number with no method is not evidence.

The data protection position matters most for digital and addressable inventory. If audience measurement or targeting involves personal data, the controller, the lawful basis and the retention period should all be documented. Where a supplier's partner has been the subject of enforcement, the ICO's decision notices are the place to confirm it rather than relying on the supplier's summary.

The planning position should state whether each site relies on deemed consent or express consent, and for digital formats whether the display meets the brightness and dwell conditions that apply. This is where a cheap site can become an expensive one.

When does a comparison table mislead you?

Comparison tables mislead when the columns are chosen by the supplier being compared, or when the rows are not like for like.

A 48-sheet on a busy arterial road is not comparable to a digital screen in a shopping centre, even if both are priced per two-week period. The audience, the dwell time and the creative constraints differ.

Tables also mislead when they mix rate card with net rate. One supplier's published price and another's negotiated price will make the second look better for reasons that have nothing to do with value.

Geography is the third trap. A national average hides the fact that most of the value sits in a handful of sites. Ask for the site-level split, not the average.

If you are building a shortlist across several regions, our out of home advertising best providers in England piece shows how we group providers by coverage pattern so that the comparison stays fair.

Before and after: what a weak review looks like next to a strong one

Read the table left to right. The left column describes what most supplier-supplied reviews contain. The right column is what you should be able to assemble yourself before a decision.

How should agencies and brands split the work?

Brands usually own the risk appetite and the creative. Agencies usually own the plan, the negotiation and the paperwork.

That split only works if the agency has the data rights position in writing. Media agencies buying digital out of home often sit between a media owner, a measurement vendor and a client's own data.

The LinkedIn resources for agencies cover platform-side teams, but they are not the right source for OOH. For OOH agency structures, Outsmart and the IPA publish more relevant guidance.

For brands running their own buying, the practical rule is to keep one person accountable for the evidence pack. If nobody owns it, nobody checks it.

For agencies pitching out of home to clients, our out of home advertising agency reviews in England piece covers what clients now ask to see during a pitch, which is a useful checklist before you present a plan.

Where does digital out of home fit in a review?

Digital out of home is where the review gets hardest, because the inventory behaves like a screen network and the measurement behaves like online media.

Know what you are comparing against. A Display Network definition from Google Ads describes the online equivalent, but it is not the benchmark for digital out of home. Route is the industry currency for audience measurement, and Outsmart publishes guidance on verification.

Digital out of home borrows that language, so buyers ask about targeting, frequency and verification in a channel once sold by poster site.

A digital panel is a physical object in a specific place. Its value comes from that place, not from audience data layered on top.

If a supplier sells the data, not the place, ask what the place is worth alone. Ask too whether each screen is sold alone or in a loop, since that changes frequency and price.

For 2027 planning, this matters because digital sites are being refreshed and recontracted now. Our out of home advertising: England market guide for 2027 looks at how those contract cycles are likely to affect availability and pricing. That forecast is based on our market guide for 2027, published in 2026.

A sample scorecard for out of home reviews

A defensible method has fixed weights, published before the providers are scored, and a rule for missing evidence.

We use four categories: inventory quality, measurement credibility, compliance and commercial terms. Each is scored against written criteria, and a missing document scores zero rather than being ignored.

That last point is the one buyers most often get wrong. If a supplier will not provide the planning position, the correct score is not "unknown" but "fail", because you cannot buy what you cannot verify.

Scores are also time-stamped. A provider that scored well last year may have lost a key site or changed measurement vendor. A review without a date is a review you cannot audit.

Common questions

Are out of home advertising reviews trustworthy?

Some are, if they name sites, date their figures and state their method. Treat any review that names no sites and cites no source as a sales document. The test is whether you could reproduce the conclusion from the evidence given.

Do I need planning consent checks for a digital billboard?

Yes. Advertisement control under the Town and Country Planning Act 1990 and the 2007 Regulations for England sets out when consent is needed and what conditions apply. A supplier should be able to confirm the position for each site in writing.

How often should a provider review be refreshed?

At least annually, and immediately after any change of media owner, measurement vendor, contract term or format. Digital sites are recontracted on multi-year cycles, so availability can shift within a single year.

What if a supplier refuses to share measurement methodology?

Treat it as a failed check rather than a gap to fill later. If the audience number cannot be explained, the price cannot be justified, and the comparison against other providers becomes meaningless.