What is Share of Voice (OOH)?
Share of Voice (SOV) in Out-of-Home advertising refers to your brand's proportion of total advertising impressions or spend within a specific outdoor media category, geography, or time period, relative to all competitors advertising in that same space.
For example, if your brand receives 150,000 impressions on UK motorway digital billboards in a month, and total impressions across all advertisers on those same sites total 1 million, your SOV is 15%.
Why SOV Matters in OOH
SOV is a critical competitive metric because OOH operates in shared, high-traffic environments. Unlike owned channels, outdoor media spaces are finite – a billboard can only display one advertiser at a time (or rotate through several). Your visibility directly competes with rival brands for the same audience attention.
High SOV correlates with increased brand recall, message frequency, and market perception of brand dominance. In crowded categories (automotive, FMCG, retail), achieving dominant SOV can meaningfully shift consumer behaviour.
How SOV is Calculated
SOV can be measured by:
- Impressions: Your OOH impressions ÷ total category impressions × 100
- Spend: Your OOH budget ÷ total category spend × 100
- Coverage: Your number of sites ÷ total available sites in category × 100
Different OOH formats (digital, static, transit, roadside) may have distinct SOV calculations, so segment by channel for accuracy.
Practical Application
Brands typically aim for SOV at or above their target market share. If you hold 20% market share but only 10% SOV, you're under-investing relative to competitors. Conversely, maintaining 25% SOV with 20% market share can help drive growth.
SOV is especially valuable in:
- Launch campaigns: High SOV establishes immediate brand presence
- Competitive markets: Demonstrates commitment and visibility
- Regional strategies: Dominates specific UK regions or cities
- Category defence: Prevents competitor encroachment
SOV vs. Share of Market
Don't confuse SOV with market share. SOV measures advertising presence; market share measures actual sales or volume. However, sustained high SOV typically drives market share growth over time.
Measurement in Modern OOH
Digital OOH platforms now provide real-time SOV data through programmatic buying and impression tracking. Traditional static OOH requires estimation based on site inventory and booking data. Connect Media Group can access detailed SOV analytics across major UK OOH networks to benchmark your performance.