When allocating media budgets, it's not just about which channel delivers the highest overall return. It's about where the next marketing dollar will have the most impact. This is what marginal ROI reveals—and it shows that Out-of-Home is often underestimated.

OOH Delivers the Highest Marginal Returns

According to a 2025 study by Keen Decision Systems, OOH achieved a marginal ROI (mROI) of $7.58. In other words, every additional dollar invested in OOH returned $7.58 in incremental revenue.

By comparison:

• Print: $7.18
• Radio: $6.61
• TV: $6.53
• Average across all media: $5.52

Marginal ROI doesn't measure the average performance, but rather the value of the next incremental investment. This is especially relevant in saturated channels like search, social, and streaming, where incremental returns have diminished. OOH, by contrast, still shows substantial room for growth.

OOH's Untapped Efficiency

The Keen analysis also compared OOH's average ROI: $1.58 across all industries. This contrast with its $7.58 marginal ROI highlights how underutilized the channel has been. While past investments may have yielded modest results, each new dollar brings much stronger returns.

This points to an opportunity: Reallocating budget to OOH could significantly improve campaign efficiency, especially as other channels begin to plateau.

Where Other Channels Plateau, OOH Scales

Digital formats dominate many companies' media plans today. But studies show that these channels are often oversaturated: Search, social, and video advertising already absorb over half of total ad spend. As a result, further investments yield only marginal gains.

OOH demonstrates the opposite. Due to its underrepresentation in most media strategies, even small budget increases can produce outsized effects. With strong marginal returns and ample headroom, OOH stands out in contrast to channels that have already hit their limits.

Justin Jefferson, VP of Strategy at Keen, puts it clearly: OOH outperforms other channels in driving incremental returns. Marketers who shift budgets away from saturated platforms into OOH improve the overall efficiency of their media mix.

Why Small Increases in OOH Already Make a Difference

The OAAA's 2024 "Incremental Steps" study examined what happens when brands gradually raise their OOH share. It found that even small increases deliver a large portion of the total possible impact. Examples across industries:

• Automotive: From 1% to 2% OOH share yields 75% of the maximum potential impact on brand awareness.
• CPG Food: From 1% to 4% delivers 70% to 80% of potential sales uplift.
• Retail Grocery: From 8% to 12% yields more than 60% of the total achievable lift.

The trend holds across KPIs—whether it's awareness, consideration, purchase intent, or sales, the first few percentage points bring the biggest results.

What This Means for Media Planning

The data shows that even modest reallocations of just 1 to 2 percent of budget toward OOH can result in meaningful gains in performance and efficiency.

OAAA especially recommends this approach for small to mid-sized brands, encouraging a shift of funds from saturated channels like TV and digital to OOH. Importantly, this isn't about increasing total spend—it's about making better use of existing budgets.

With an incremental approach, brands can test and refine their OOH strategy with minimal risk. In most cases, the uplift is evident quickly.

Conclusion

OOH proves that major results don't always require major changes. Especially in today’s oversaturated digital landscape, Out-of-Home offers a high-potential alternative with fast, measurable impact. Starting small can lead to long-term gains.