Route vs. Geopath: How OOH Audience Measurement Works in the UK and the US

If you sell or buy out-of-home media on both sides of the Atlantic, you are trading against two different measurement currencies. In the UK, campaigns are planned and traded on Route. In the US, the equivalent authority is Geopath. They answer the same question — how many people saw this ad? — with different governance, different methods, and, as of 2026, very different timelines: the US system is in the middle of being rebuilt.

Direct answer: Route is the UK's Joint Industry Currency (JIC) for out-of-home — a not-for-profit owned collectively by advertisers, agencies and media owners — publishing five campaign measures: reach, impacts, frequency, cover and GRPs (Route FAQ). Geopath is the independent, third-party measurement authority for US OOH, providing impressions, reach and frequency for audited formats (Geopath). In March 2026, Geopath and the OAAA selected Ipsos to run a next-generation measurement pilot launching in the second half of 2026, with a transition expected to begin in 2027 (Geopath blog).

What is Route, and how does it measure OOH audiences?

Route is the UK's audience measurement body for out-of-home advertising, structured as a Joint Industry Currency: an independent, not-for-profit company owned by the industry itself — advertisers, agencies and media owners together — so that no single side controls the numbers (Route FAQ).

Mechanically, Route starts from a database of advertising displays that records each frame's exact location and its angle to the road. It combines this with travel-behaviour data — counts of people moving along each street and route where displays sit — and then adjusts those raw passing counts to reflect a realistic estimate of how many people will actually see the advert, not merely pass it (Elonex: How we measure audiences with Route). That visibility adjustment is the heart of the system: an impact in Route is a likelihood-to-see figure, not a traffic count.

For any campaign, Route outputs five measures: reach (unique people who see the campaign), impacts (total times it is seen), frequency (average views per person reached), cover (proportion of the target audience exposed) and GRPs (Connect Media Group: Route explained). Route covers the large majority of professionally sold OOH inventory in the UK, from billboards to bus shelters and street furniture.

What is Geopath, and how is it different?

Geopath is the US industry's impartial, third-party authority on OOH audience measurement, providing impression data for audited OOH formats, alongside reach and frequency (Geopath). We've covered how a Geopath rating is actually constructed in What Is Geopath, and How Is an OOH Rating Actually Built? — the short version is that, like Route, it models audiences from location, movement and visibility data rather than counting devices or plays.

The structural difference is governance and geography. Route is a JIC with formal joint ownership across the UK industry; Geopath is an independent non-profit serving the US market in close partnership with the OAAA, the national trade body. In practice this shapes how each currency evolves: Route updates inside one national framework, while the US system moves through industry-association initiatives — which is exactly what is happening now.

What changes in 2026: the Ipsos next-generation pilot

In March 2026, Geopath and the OAAA announced that Ipsos will support an industry pilot of a next-generation OOH measurement system, launching in the second half of 2026. The pilot will evaluate updated methods for estimating impressions, reach and frequency across multiple formats and environments (Geopath blog, 31 March 2026). Industry reporting anticipates an orderly transition from the current Geopath system to the new framework beginning in 2027, with full adoption targeted for 2028 (Media4Growth).

For anyone reporting against US OOH data, the practical implication is that the currency under your numbers is scheduled to change. Campaign reports, historical comparisons and sales materials built rigidly around today's Geopath outputs will need to translate — a reason to keep the measurement layer of your reporting flexible rather than hard-coded.

What should a media owner report against each currency?

A currency tells the market what your inventory is worth; it does not report your campaigns for you. Media owners still have to put the two layers together for every advertiser:

The audience layer comes from the currency — Route impacts and cover in the UK, Geopath impressions in the US. This is what buyers plan and trade against, and your campaign report should speak the same language as the plan.

The delivery layer is yours: which frames ran, when, how many plays, at what share of time — the operational proof that what was traded actually happened. In digital OOH this is where plays and impressions get conflated, a gap we unpacked in Plays vs. Impressions: What You're Actually Buying in DOOH.

Advertisers increasingly expect both layers in one view, tied together honestly — currency audience figures next to delivery proof, with nothing double-counted. What that finished report looks like from the buyer's side is the subject of What Advertisers Now Expect From an OOH Campaign Report.

FAQ

Is Route data available for every OOH site in the UK? No. Route covers the vast majority of professionally sold OOH inventory, but not every individual site is measured. For unmeasured inventory, media owners typically report delivery data alongside the nearest comparable audience evidence, clearly labelled.

Do Route and Geopath numbers mean the same thing? They are built on similar principles — modelled, visibility-adjusted audience estimates — but they are different systems with different inputs and definitions. A Route impact and a Geopath impression should never be summed or directly compared in one report without saying so.

Will Geopath numbers change during the Ipsos pilot? The pilot launching in late 2026 runs alongside the current system; the anticipated transition begins in 2027 with full adoption targeted for 2028. Until then, today's Geopath data remains the trading currency in the US.

What should international campaigns use? Report each market against its own currency — Route in the UK, Geopath in the US — and keep a clearly labelled delivery layer (plays, uptime, share of time) consistent across markets, since that layer is yours and travels everywhere.

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At Sifra, this is the Mobility work: campaign reporting that puts currency audience figures and delivery proof in one dashboard advertisers actually trust. Data, made visible.

Curious what yours would look like? We'll build you a free mock campaign dashboard shaped around your own inventory — no commitment.