A quick-service restaurant brand ran a standard OOH campaign and saw a 365% lift in sales versus unexposed consumers. Impressive on its own. But when that same brand retargeted billboard-exposed audiences with mobile ads, the lift jumped to 729%. The billboard creative didn't change. The audience didn't change. The only difference was what happened after the impression.

This pattern repeats across verticals. Some Agility clients running precision brand advertising campaigns saw 15% lift in sales when they ran a billboard on its own. The same client who extended those campaigns with cross-channel retargeting saw 40+% sales lift, nearly three times the result for a fraction of additional cost.

Does retargeting improve billboard advertising results? Yes, significantly. The mechanism is audience priming. OOH exposure makes consumers 48% more likely to engage with a subsequent digital ad for the same brand.

Billboards Still Command Attention (But Leave Money on the Table)

Out-of-home advertising is not a relic. It's a $9B+ industry that is still growing. Eighteen consecutive quarters of growth confirm this isn't a blip. Brands like Apple, McDonald's, Amazon, and Google rank among the top 10 OOH spenders because the format works.

The brand recall numbers explain why. A Nielsen study found OOH delivers a 55% brand recall rate, making it one of the most effective channels for driving awareness, compared to roughly 35% for digital display. Physical presence creates stronger memory encoding than pixels on a screen.

Consumers act on what they see. According to OAAA and Morning Consult research, 68% of U.S. adults notice OOH ads on their way to shop, and 42% say those ads directly impact their in-store purchase decisions. The OAAA reports that every $1 spent on OOH generates approximately $5.97 in product sales, outperforming digital display, print, and radio.

So, it works! The problem is what happens after the impression. Most brands buy the billboard, measure reach, and move on. They treat OOH as an awareness play with no continuation strategy. Lift that could have been several times higher sits there, uncollected.

OOH creates a primed audience. But that audience has a short shelf life if there's no digital touchpoint to follow.

The Leaky Funnel: How OOH Awareness Converts for Your Competitors

The uncomfortable truth about standalone billboard campaigns is that they generate intent, but without a follow-up system, that intent is captured by someone else.

OAAA research shows that 76% of U.S. adults take action on their mobile device within 60 days of seeing an OOH ad. Half of those actions are online searches. They're searching for the brand, the product category, or the problem the billboard addressed.

And 74% of mobile device users took action on their phones after seeing a DOOH ad. 44% searched for the advertiser, and 38% visited the advertiser's website.

Without a digital retargeting strategy, the consumer who just saw your billboard searches your category on Google. Your competitor's paid search ad appears first. The consumer clicks. Your billboard spend just funded someone else's conversion.

Traditional OOH operates on a single-impression model: one exposure, no audience tracking, no continuation. You build brand awareness and prime purchase intent, then hope the consumer finds you on their own. In a market where every competitor is running search and social, hope is not a strategy. You are essentially paying to fill the top of the funnel for brands that show up in the middle.

What Billboard Retargeting Actually Does (And Why It Multiplies Results)

OOH retargeting with geofencing solves the leaky funnel by connecting physical impressions to digital identities. The mechanism is straightforward. Geofencing technology captures mobile device IDs (MAIDs) near billboard locations, creating a retargetable audience segment of consumers who were actually exposed to the OOH creative. Agility layers behavioral, purchase, and location data on top of that segment to build full persona profiles, so retargeting reflects not just who walked by, but who your ideal buyer actually is.

Once you have that segment, you can serve digital ads (display, mobile, CTV, native) to the same people who saw the billboard, reinforcing the message across channels. This isn't theoretical. Neuroscience actually supports it.

Research by Ocean Outdoor and Neuro-Insight found that memory encoding levels for online content were 48% higher among consumers who had seen the same brand on DOOH first, compared to those who had been primed by the same brand on TV. Beyond creative matching, mere exposure to DOOH led to 36% higher memory encoding for subsequent mobile advertising, regardless of whether the mobile ad matched the DOOH campaign. The researchers called this the "congruence effect," the way environment and brain state during OOH exposure prime stronger responses to advertising on mobile devices.

That congruence effect is the engine behind the lift multiplier. The billboard creates brand familiarity and primes the audience. Digital retargeting converts that familiarity into action. Cross-channel frequency builds deeper memory encoding because the same persona encounters the brand on a billboard, then on their phone, then on connected TV.

This is why OOH increases the ROI of search advertising by 40% when added to a media plan. The billboard doesn't just build awareness. It makes every downstream digital touchpoint more effective. That is the halo effect in practice.

Lift Explained: What the Data Shows

The pattern is consistent across Agility's client base and the broader industry: billboards alone deliver meaningful lift. Billboards plus digital retargeting deliver dramatically more.

The IAB's OOH + Mobile Integration case studies confirm this at scale. A gaming console brand activated DOOH near electronics retailers and layered in mobile retargeting to consumers who passed the OOH units. DOOH alone increased visitation by 69%. Mobile alone produced 46%. But consumers exposed to both DOOH and mobile saw a 127% visitation lift, nearly double what either channel delivered on its own.

A major fitness brand combined high-impact billboards with proximity targeting and behavioral mobile ads. They saw a 260% lift in visitation rates from those exposed to both OOH and mobile.

This is reinforcement theory applied to media planning. A message seen in one context (a highway billboard) and then repeated in another context (a mobile ad during lunch) is encoded more deeply in memory than either impression alone. Agility measures this through incrementality testing, not last-click attribution. Last-click attribution would credit the search ad for a conversion that the billboard actually initiated. Incrementality reveals the true channel contribution and proves the billboard's role in creating the buyer.

That's the difference between precision brand advertising and performance marketing. Performance competes for existing demand. Precision brand advertising creates new buyers, then tracks them through the full journey to purchase.

How to Execute OOH Retargeting with Precision

Knowing that billboard retargeting works is one thing. Executing it with measurement-grade rigor is another. 

Build the persona before buying the billboard. 

Most OOH buys start with location. Precision brand advertising starts with the audience. Define the exact buyer persona first, including demographics, behaviors, and purchase signals, so that your retargeting can find the same people digitally. A billboard on I-15 matters only if the right audience is driving past it.

Capture exposed audiences through geofencing and MAID resolution. 

Deploy geofences around billboard locations to capture mobile device IDs of consumers who passed within range. MAID resolution connects those anonymous device signals to targetable digital identities. This is what transforms a static billboard from a one-and-done impression into the first step of a measurable buyer journey.

Mirror the billboard creative in digital. 

Message consistency is what drives the engagement lift. When a mobile ad echoes the billboard, the brain recognizes the pattern and encodes it more deeply. Change the creative entirely between OOH and digital, and you lose the priming effect.

Retarget across every channel the persona touches. 

Mobile display can be a starting point, not the endpoint. Extend retargeting to CTV, native, audio, and programmatic display. The goal is cross-channel frequency. The persona sees the brand on a billboard Monday morning, on their phone Monday afternoon, and on their connected TV Monday evening.

Measure incrementally, not through last-click. 

Set up experiments with one segment exposed to billboards plus retargeting and another exposed only to billboards. Then, compare lift across all three. This is how you prove to a CFO that the billboard campaign created $4M in incremental revenue instead of pointing at a last-click report that credits Google search. OOH incrementality testing is the only way to measure billboard campaign lift with certainty.

Your billboard campaign is already creating buyers. The question is whether you're reinforcing your brand and capturing them or letting them convert to a competitor. Precision brand advertising connects OOH impressions to digital personas and tracks the full buyer journey to purchase.

Talk to an Agility expert about connecting your brand advertising spend to measurable revenue. Create new buyers. Grow with certainty.

Frequently Asked Questions

Does retargeting actually improve the results of my billboard campaign, or is the lift just from the billboard itself?

Yes, and significantly. Billboards alone drive meaningful brand recall and intent, but without a digital follow-up strategy, that intent can be captured by a competitor. Agility's data shows clients running OOH alone saw a 15% lift in sales metrics. The same clients who extend their campaigns with cross-channel retargeting, serving ads to the exact billboard-exposed audience across CTV, mobile, native, and display, saw 40%+ growth.

How do we measure the incrementality of OOH retargeting vs. the billboard alone?

Incrementality testing is the only rigorous way to answer this question. This is the measurement methodology Agility uses across all precision brand advertising campaigns, producing CFO-ready reporting that shows the exact revenue impact of billboard spend, not just last-click attribution that credits Google search for conversions your OOH already drove.

If we're already running brand advertising on paid social, why do we need OOH retargeting?

Social platforms only reach audiences while they're using those apps. 61% of online time is spent on the open internet. OOH retargeting bridges physical presence with the open internet, reaching the same buyer persona across CTV, native, audio, display, and mobile apps outside the social ecosystem. The combination is additive, not redundant: social builds awareness within its walled garden, OOH creates physical brand familiarity, and cross-channel digital retargeting reinforces both across every surface the persona touches. Agility's precision brand advertising platform treats all of these channels as a single unified system, targeting the same persona, optimizing creative in real time, and measuring the full buyer journey from first billboard impression to purchase.