What is Likelihood to See?
Likelihood to See (LTS) is a predictive metric used in out-of-home (OOH) advertising to estimate the probability that a member of your target audience will actually view an advertisement placed in a specific location. Rather than assuming everyone passes a billboard or transit ad, LTS uses data-driven models to calculate realistic exposure based on audience movement patterns, dwell times, and site-specific variables.
Why LTS Matters
OOH advertising spend requires significant capital investment, making accuracy in audience delivery critical. LTS allows media planners to:
- Validate site selection before committing budget to premium locations
- Compare venues objectively using standardised metrics rather than footfall claims alone
- Optimise campaign reach by identifying sites with highest exposure probability for specific demographics
- Justify investment to clients with evidence-based predictions
In the competitive UK market, where prime billboard space commands premium rates, LTS helps agencies move beyond vanity metrics like "daily impressions" to meaningful audience delivery.
How LTS is Calculated
LTS combines multiple data sources:
- Foot traffic data: Actual movement patterns from mobile data, footfall counters, or transport authority records
- Dwell time: How long people typically spend in view of the ad
- Audience targeting criteria: Age, demographics, and behaviour filters matched against passing audiences
- Visibility factors: Sightlines, angles, obstructions, and competition from other ads
- Temporal patterns: Rush hour peaks, weekend variations, seasonal changes
The output is typically expressed as a percentage (e.g., "65% LTS") representing the proportion of your target audience likely to see the ad during the campaign period.
When to Use LTS
LTS is particularly valuable for:
- Geo-targeted campaigns promoting local events, retail locations, or regional services
- High-value placements where budget justification is essential
- Audience-specific buys targeting commuters, shoppers, or specific age groups
- Campaign planning to estimate total reach before media buying
- Benchmarking comparing OOH performance against digital channels
UK media agencies increasingly use LTS as standard practice, particularly when working with major advertisers or premium transit placements on London Underground, National Rail, or motorway sites.
LTS vs. Other OOH Metrics
While Opportunities to See (OTS) measures raw, unfiltered passing audiences, LTS applies realistic filtering for actual target audience visibility. This makes LTS more conservative but more commercially honest – a key distinction when pitching campaigns to data-conscious clients.
Best Practice
When evaluating LTS data, verify the methodology behind calculations. Reputable sources like JCDecaux, Clear Channel, and transport authorities publish transparent LTS models. Cross-reference with independent footfall data where possible.