Brand marketing does not show its returns in 30 days. It builds a reservoir of awareness and intent that makes every future pound of performance marketing more efficient. Measure it on a 12 to 24 month horizon or you will always undervalue it.
Performance marketing is easy to measure because the feedback loop is short. Click today, convert today. Brand marketing is harder because the feedback loop is long. A consumer sees your TV ad in January and buys in April. The conversion gets credited to the paid search ad they clicked in April, and your TV investment looks like it did nothing. This is the core measurement problem in brand marketing, and it distorts spending decisions across the industry.
What brand marketing actually does
Brand marketing builds salience (the chance your brand comes to mind when someone has a relevant need), preference (favouring your brand over competitors), and trust. None of these translate immediately into a sale. They build a base of latent demand that converts over months and years. Without brand investment, performance channels gradually become more expensive because you are only catching people who already knew you, not building a pool of future buyers.
The adstock effect
Advertising has a carry-forward effect called adstock. When you run a TV or video campaign, the impact does not appear only in the week the ad runs. It decays gradually over weeks or months as memory fades. This means a campaign that runs in week 1 is still generating some effect in week 8. Marketing Mix Models capture adstock explicitly, which is one reason they are better at valuing brand spend than any short-window attribution tool.
- Short-lived adstock (half-life of 1 to 2 weeks): typical for tactical promotional messages.
- Medium adstock (half-life of 3 to 6 weeks): typical for product-level brand advertising.
- Long adstock (half-life of 8 to 16 weeks): typical for brand-level campaigns focused on emotion and identity.
- Your MMM can estimate the adstock decay rate for each of your brand channels, giving you a more accurate view of their true contribution.
Metrics that capture long-term brand value
Short-term ROAS is the wrong metric for brand. Instead, track branded search volume over time: when your brand investment is working, more people search for your brand by name, which indicates growing awareness and intent. Track direct traffic as a proxy for top-of-mind awareness. Track Net Promoter Score or brand consideration from regular survey data. And track the efficiency of your performance channels over time: if your brand is doing its job, your paid search cost per click and cost per acquisition should gradually improve as more people already know you.
Research from the IPA Effectiveness Databank shows that brands with a 10 percentage point share of voice advantage over their market share tend to grow their market share by about 0.5 percentage points per year. The brand multiplier is real but slow. It rewards patience.
Using Marketing Mix Modelling to value brand
A well-built Marketing Mix Model attributes revenue to brand channels using adstock-adjusted contributions. It shows what share of this quarter's sales came from brand activity run in previous quarters. This is the most rigorous way to demonstrate brand ROI because it connects the investment to actual sales, even with a time lag.
Balancing brand and performance spend
The optimal split between brand and performance spend varies by category and business maturity. A general rule, drawn from IPA research, is 60 percent brand to 40 percent performance for established consumer brands. Newer brands, or those in less competitive categories, may need to weight performance more heavily early on. The right split for your business should be driven by your MMM output, not a rule of thumb.
How do I convince a finance team that brand spend is worth it when I cannot show a clear return in 30 days?
Use a 12-month payback model. Show the cumulative revenue contribution of brand campaigns over 4 to 6 quarters, using MMM data. Then show what happens to that revenue trajectory if brand spend stops: performance efficiency deteriorates, acquisition costs rise, and branded search volume drops. Put a cash value on each of those effects.
We run performance-only campaigns. How do we know if we are leaving brand value on the table?
Track your branded search volume trend over 12 months. If it is flat or declining while your performance spend is growing, you are likely not building enough awareness to fill your future demand pipeline. You are harvesting existing intent rather than growing it. That works until it does not, typically when a competitor invests in brand and begins to take share of mind.
Should we measure brand and performance in the same MMM?
Yes. Separating them misses the interaction effect where brand investment makes performance marketing more efficient. A combined model shows the full picture: how brand spend reduces paid search CPA over time, and how cutting brand spend eventually raises the cost of performance acquisition. That interaction is where a lot of the value of brand investment actually lives.