What is the Halo Effect in Advertising and How Do You Measure It?
The halo effect is the extra lift a campaign gives to products, channels or markets it was never aimed at. You can't see it in last-click reports, but you can measure it with geo tests, mix modeling and brand lift.
The halo effect in advertising is the good a campaign does outside its own brief: a shampoo ad that also sells conditioner, a TV spot that fills up your branded search, a campaign in one country that drives demand next door. Brand media creates most of it, performance channels usually collect the credit, and last-click attribution rarely sees it at all.
Where the Term Comes From
The phrase comes from psychology. In 1920, Edward Thorndike noticed that army officers rating their soldiers couldn't keep their judgments separate. If an officer liked a man overall, he scored him higher on everything, from intelligence to physique. Thorndike wrote it up as "A Constant Error in Psychological Ratings," and the name stuck.
Brands work the same way. Once people think well of a brand, that feeling spills over into everything it sells.
Three Kinds of Advertising Halo
Across a product range. Advertise one product and its siblings sell more too. When Ebiquity analysed UK TV campaigns from 2006 to 2011 for Thinkbox, it found that 38% of TV's sales effect landed on products that weren't in the ad. The direction of the halo matters as well. Nielsen found the lift from a brand extension back to the parent brand is much stronger than the lift from the parent out to the rest of the range.
From brand to performance. This is the one most marketers feel without being able to prove. A TV, CTV, out-of-home or video campaign gets people interested. A few days later they search your name, type in your URL or click a retargeting ad, and the sale shows up in your performance channels. Search gets the credit, even though the brand campaign did the persuading.
From one market to another. People travel, speak the same languages and use the same global platforms, so media bought in one country rarely stays there. If a multinational plan ignores this, it ends up either counting the same reach twice or starving the market that's actually doing the work.
Why Attribution Gets It Wrong
Most attribution gives the credit to whatever someone clicked last. That shortchanges brand media, because its results end up in another channel's report. It also flatters the channels that simply pick up demand someone else created.
eBay found this out the hard way. In a large field experiment, the company switched off its paid search ads on brand keywords like "eBay." Economists Tom Blake, Chris Nosko and Steven Tadelis found that those ads had no measurable short-term benefit. People who were already looking for eBay just clicked the organic link instead. Sales that came from the strength of the brand had been credited to search for years. That's the halo effect, booked to the wrong line.
How to Measure the Halo Effect
- Run a geo experiment. Pause or cut media in a handful of matched regions, keep it running everywhere else, and compare total results across every product and channel. Google's free, open-source Meridian GeoX supports this kind of test and can feed the results into a marketing mix model. Our guide to incrementality testing walks through the setup.
- Build a mix model at the right level. Media mix modeling can show how spend in one channel moves results in another, including products you never advertised. That only works if the model covers the whole brand or range, not one product at a time.
- Watch brand and search lift. A brand lift study tells you whether awareness and consideration moved. Branded search in regions that saw the campaign, compared with regions that didn't, is one of the quickest early signals.
- Agree the KPI before launch. Measure total revenue or total new customers across the brand. A report scoped to a single product will never find a halo.
Using the Halo Effect in Global Media Planning
At Criterion Global, we plan brand and performance media together rather than as rival budgets. The Criterion Global Budget Blueprint℠ sets advertising budgets market by market, with brand and performance spend in the same model, so the demand brand media creates is counted when performance budgets are decided. For companies with several product lines, portfolio media strategy works out which product should carry the brand for the others.
Barbie® is the long-term version of this. Criterion Global planned and bought media for Mattel's "I Can Be…™" campaign, which rebuilt Barbie®'s brand equity years before the 2023 film went on to take $1.44B at the box office. The Barbie® case study shows how that investment kept paying back long after the campaign that funded it ended.
If you want brand and performance media planned against one set of numbers, talk to our international media planning and buying team.