The world of digital marketing is constantly evolving, but in the last few years we’ve seen a pretty steep change curve. I could write a list as long as my latest skincare routine of all the factors that have hit our world recently, but here’s the shortlist that actually matters for this article:
And it’s the perfect storm behind why we’ve seen such a jump in brands investing in influencer marketing (spend here is expected to exceed £3 billion in the UK alone by 2027).
You’re probably reading this as a seasoned marketing professional who’s totally aligned with why investing time, money and effort into influencer marketing right now is critical for the growth of a brand in today’s world. You live and breathe this stuff. The problem is the person who holds the purse strings, and judges every single pound of spend against its return probably doesn’t.
The likelihood is that your CFO doesn’t actually care about influencer marketing. They don’t care about reach, engagement, vibes, or the fact that a creator with 40k followers “really gets the brand.” What they care about is one question, asked in about four different ways across the quarter:
Can you actually prove this spend was attributed to any sales?
Not “did it help.” Not “do you feel good about the relationship.” Attributed. As in: show me the pound, and show me the line connecting it back to this spend, or the budget line gets a red pen through it.
Because underneath it all is a single, entirely reasonable demand for proof. And the honest answer is: for some of it, we can prove it brilliantly but for a lot of it, we genuinely can’t. And not because it didn’t work, but because the tools doing the measuring were never built to see it.
So before we go further, a quick definition check, because this is where most of the confusion actually starts.
Brand influencer activity is “Tell.” It’s reach. It’s awareness. It’s introducing your product to people who’ve never heard of you. It is, by design, upper-funnel and it should never, ever be judged on last-click conversion, in the same way you wouldn’t judge a billboard on how many people scanned a QR code driving past it at 60mph.
Performance influencer activity is “Show” and “Prove.” It’s aimed at people who already know who you are, and its job is to move them to buy. Conversion is genuinely the goal here which is exactly why it’s the one that gets mismeasured.
Because the goal is conversion, CFOs quietly default to judging it the same way they’d judge a PPC campaign: last click, full stop, no discussion. That instinct is understandable. It’s also wrong.
Once you separate the two, the “does influencer even work” argument gets a lot less circular.
Now let’s get into why performance influencer specifically is so hard to prove, even when it’s working brilliantly.
Reason one: you’re being asked to compare costs that were never comparable.
UK paid social spend hit £11.5bn in 2025, up 21% year-on-year. Meta CPMs now average £8–£18, spiking above £26 in Q4. Costs are climbing across the board and every time they do, your CFO puts that Meta CPA number next to your influencer campaign cost and asks why the second one looks so much higher.
Here’s what few people flag: Meta’s number is a price for reach. Just reach. Media, and media alone. Production, agency fees and labour usually sit in a completely different line item, if they’re costed at all.
Influencer cost bundles all of it in one number… the media (their audience), the production (their content), the labour (briefing, negotiation, usage rights) and something Meta’s number will never, ever include: third-party advocacy.
A stranger recommending your product carries more weight with a buyer than you recommending your own product ever will. That trust premium doesn’t show up on either invoice. You’re not comparing two media costs. You’re comparing a rented audience to an earned one.
Reason two: the tools you’re using have massive blind spots.
Some customer journeys are, genuinely, a dream to report on. Sees content, clicks link, doesn’t get distracted by a cookie banner, converts in the same session. Full attribution. Everyone’s happy (chefs kiss). That is the floor of what influencer activity delivers. It is not the ceiling.
Treating it as the ceiling is the single biggest reason CFOs undervalue this channel and here’s what’s actually happening in the gaps:
None of this is a Silverbean excuse. It’s the industry’s own admission.
Dark social (sharing that no analytics platform can see) accounts for an estimated 84% of all online sharing. Roughly 41% of conversions are influenced but untracked by last-click models, and only 23% even get counted as an assisted conversion. TikTok and Meta have both told advertisers in 2026 to move off last-click entirely, because it under-credits upper-funnel activity by as much as 90%. And 75% of buy-side marketers admit their core measurement (attribution, incrementality, modelling, all of it) is underperforming.
So: two reasons, and they compound. You’re comparing unlike costs and measuring with a tool that structurally short-changes the channel. Of course it looks like the spend “attributed to nothing”… it was never given a fair chance to prove otherwise.
Here’s where we stop trying to prove Return on Investment from influencer activity, because ROI, calculated the way most CFOs calculate it, literally cannot answer either of the two problems above. It wasn’t built to.
Instead, we measure Return on Influence… the compounding effect of trust transfer from creator to audience, on every other channel’s efficiency, including the rising paid CAC problem we started with.
Quick analogy, because I like to paint pictures.. influencer is agriculture, not a vending machine. You’re sowing seeds. You don’t get to see the yield the same day, and if you dig the seed up every week to check on it, you kill the crop before it’s had a chance. But farmers don’t refuse to farm because they can’t see the roots… They measure soil, weather and growth rate as proxies while they wait. That’s exactly what a proper reporting model does too.
If your instinct is “sure, but influencer is a brand play, not a performance one”… fair, that used to be true. It isn’t anymore, and here’s the UK data to prove it, not just my opinion on the matter:
Consumer trust, platform mechanics and creator incentives have all matured at the same time, in the same 18 months. Which means the “prove it converts” argument isn’t the interesting one anymore. The interesting one is: now that it clearly does, how do you measure it in a way that survives contact with finance?
Knowing why proving attribution is hard doesn’t get you through the monthly finance review on its own. You need something you can put in front of a CFO that doesn’t fall apart the second someone asks “but how do you know?”
That’s the bit we’ve turned into an actual framework… a four-step approach to running a performance influencer campaign and reporting on it properly, including the exact three-layer revenue model we use to show post-click, assisted and modelled uplift.
We’ve packaged the whole thing; the campaign steps, the reporting layers, and a template you can literally lift straight into your next report, into one PDF download.
Download the Return on Influence Reporting Playbook; the 4-step framework for running and reporting an influencer campaign your CFO won’t argue with.
My bank balance, several screenshotted-not-clicked purchases, and one very confused attribution model can all confirm: this stuff is working whether GA wants to admit it or not. Us marketeers might as well get credit for it.