How is outdoor advertising measured?

how to measure outdoor advertising using various methods

Any reader of this blog will understand the powerful impact outdoor advertising has, and the many ways it can be leveraged by brands to great effect. But given the complexity of this medium, how is outdoor advertising measured? How do we know when our outdoor campaigns are returning a good ROI? Let’s take a look.

Measuring your audience

There are two main considerations with billboard and poster advertising: what is the size of the potential audience for your displays? How many of those people actually saw your ad?

There are then metrics that follow on logically from these: how many of those exposed to your messages were driven to engage with your brand? Has there been a measurable impact on sales?

Opportunity to contact

Market research company Esomar use the term Opportunity to Contact (OTC). This is a metric for measuring how many people will potentially walk past your advert and see it. This takes in to account survey data, and mobility modelling. But there’s a further element to this: Visibility adjusted contact (VAC). This refers to the amount of people who actually saw the advert during the campaign.

When measuring the effectiveness of Outdoor advertising, various different factors and data sets can be taken in to account.


This is a measure of any movement or journey on foot or by vehicle taken between various different points in the Outdoor environment. There are many ways to measure mobility: GPS tracking devices carried by survey participants, travel diaries, and recall surveys analysing the movements of participants over the previous days.

Traffic data

This is a measurement of pedestrian or vehicular traffic through a particular road section relative to the advertising sites. Transport planning data can be used to calculate ad exposure in a given area, although the quality of this data varies widely within different countries and cites. Typical data that can be drawn on includes commuting data, data on leisure activity participation, road traffic counts, and government surveys and census data.

Measuring effectiveness

Pre/post-campaign measurements

The simplest way to measure the effectiveness of outdoor advertising is to take a metric such as sales, and look at sales impact before and after running an outdoor campaign. Has there been a noticeable increase? The difficulty here is working out if there are other factors that may have created a spike (or, heaven forbid, drop) in sales. If your brand had two separate campaigns (say, Outdoor and Online) on the go at the same time it would be difficult to isolate the impact of Outdoor as brand engagement and sales may have been influenced by either campaign. What if your Outdoor campaign is extremely successful but your Online campaign is actually harming sales? It would be very hard to accurately measure outdoor advertising effectiveness in this scenario. A much better scenario would be to only run a single Outdoor campaign and keep all other brand activity stable. Then the results (or lack of) of your campaign would be plain to see.

Coupon codes, sales events, etc

There are other, more involved techniques for measuring effectiveness. Ad-specific coupon codes, discount vouchers, URLS, QR codes, etc., are a great way to measure the effectiveness of outdoor advertising. If they are limited to the outdoor ad itself, then any engagement can be measured with a large degree of certainty that the results reflect the effectiveness of the ad.

Use of slogans specific to the outdoor environment can be useful here; audiences are likely to google slogans that make an impact on them, gaining valuable insight into how memorable your messaging is, and the extent to which it is driving engagement.

Signkick can be your guide through each step on the way to running a successful Outdoor campaign. Get in touch with us today to understand more about how you can measure the effectiveness of your campaigns.