The short answer: Most influencer reports carry a dozen metrics and only four of them change a decision: cost per thousand impressions, cost per acquired customer including fees, return on ad spend against trackable links and codes, and the share of seeded creators who convert into affiliates. The rest are context or vanity. As reference points from verified Augmentum Media campaigns, cost CPMs have ranged from £2.49 on seeded nano and micro programmes to £16.34 on mid-tier paid, customer acquisition cost has come in under £13.96 including all fees, and seed-to-affiliate conversion typically runs at 15 to 25%.

What are the key influencer marketing KPIs?

Twelve get reported. Four decide anything.

As of September 2026 there is still no trustworthy published benchmark set for this channel, which is why every figure on this page traces to a named campaign rather than to an industry average. Almost every published list on this subject is a list of things you can count. That is not the same as a list of things worth acting on, and the gap between the two is why influencer reports get longer every quarter while the decisions they inform stay the same.

Here is the full reporting set, with an honest label on each.

Augmentum Media reports the four marked decision-grade against every programme, and treats the rest as supporting evidence rather than headline numbers. The argument for why those particular four, and how they cover each other's blind spots, is set out in how to measure influencer marketing ROI. This page is the reference table: every metric, what good looks like, and where the number comes from.

What is a good CPM for influencer marketing?

The most useful benchmark on this page, because it is comparable across channels and hard to fake.

Cost CPM is total programme cost divided by impressions, times a thousand. Not the creator's rate card. Not what an agency quoted. What you spent, over what it reached.

Those are all Augmentum figures from named campaigns rather than survey averages, which matters because the published benchmarks in this category are almost entirely self-reported. The spread is the finding: the same objective, bought two ways, differs by roughly six times. The £16.34 was not a failure, it beat its own target by 18% and delivered a 5.3% average engagement rate against a 1.5 to 2% benchmark. It is simply what reach costs when you buy it rather than earn it.

If you take one number from this page, take the ratio rather than any single figure. A seeded programme should be running at a small fraction of your paid social CPM. If it is not, the problem is the programme, not the channel.

What is a good cost per acquisition from influencer marketing?

The one your margin supports, and the one you calculate with the fees left in.

There is a persistent trick in how this gets reported. Excluding platform and agency fees produces a flattering number that does not correspond to anything leaving the bank. On a 20-month Fussy programme, the verified figures were under £13.96 including all fees and £5.52 excluding them. Both are true. Only the first is the cost of a customer.

The same programme ran at 5.12x ROAS across 11,500+ new customers, and a Mother's Earth programme in the Netherlands ran at 5.41x with EUR 120k+ in affiliate revenue. Treat those as evidence that the channel can hit paid-media-grade efficiency, not as a target you should expect in month one.

What is the seed-to-affiliate rate, and why does nobody report it?

Because it is slow, it is unflattering early, and no dashboard calculates it for you.

It is the share of creators you seeded who go on to become active affiliates or ambassadors. Typical range is 15 to 25%, rising to around 35% on the best-run accounts. It is the only metric on this page that predicts next quarter rather than describing last one.

A ROAS figure tells you whether last quarter worked. The seed-to-affiliate rate tells you whether next quarter will, because a programme converting a quarter of its seeded creators is compounding and one converting 2% is renting attention at a price that rises every year.

Augmentum Media plans every programme around that band, and it is the number to ask any agency or platform for before signing anything. Most cannot produce it, which is itself informative.

Which influencer marketing metrics are vanity?

Engagement rate, follower count and earned media value reported on its own. Each has a legitimate narrow use and each is routinely used outside it.

Engagement rate falls predictably as audience size rises, so a nano creator will always beat a macro creator on it regardless of commercial outcome. It is useful for spotting a fake account or a dead audience. It is useless for comparing tiers or for justifying a budget. The tier comparison it fails at is done properly on CPM in micro vs macro influencers.

Follower count describes potential reach on a platform where distribution is decided by an algorithm. On TikTok especially, recent view counts predict performance far better.

Earned media value is the most dangerous, because it is a real calculation that can be quietly inflated by choosing a generous rate for what the equivalent paid placement would have cost. Reported next to what the programme actually cost, it is honest and useful. Reported alone, it flatters. The formula and the honest way to present it are in earned media value.

How often should you report each metric?

Different metrics move on different clocks, and reporting them all monthly is why influencer reports feel busy and say little.

1. Weekly: content volume, posts live, creators onboarded. Operational numbers that tell you whether the machine is running.

   
   

2. Monthly: cost CPM, trackable revenue, ROAS, cost per creative. Enough time has passed for these to mean something and not so much that a problem hides.

   
   

3. Quarterly: CAC including fees, seed-to-affiliate rate, repeat rate on creator-acquired customers. These are slow by nature and reading them monthly produces noise that gets acted on.

   
   

4. Never as a headline: engagement rate, follower reach totals, earned media value without cost beside it.

The lag matters most on the quarterly set. Cutting the measurement window on the last posting day understates a programme that is still converting, which is the single most common way a working programme gets cancelled.

What should an influencer marketing report actually contain?

One page, six numbers, and the comparison that gives them meaning.

Cost CPM this period against last. CAC including fees against your blended CAC from every other channel. ROAS on trackable revenue, stated as a floor. Content volume with a note on what that content would have cost to produce conventionally. Seed-to-affiliate rate, tracked as a trend rather than a level. And the total programme cost, with product at landed cost, shipping, fees and internal time all included.

The comparison line is what turns a report into a decision. A CPM with nothing beside it is trivia. A CPM next to your paid social CPM is an argument for a budget.

What most brands get wrong about influencer KPIs

They measure the channel against itself.

An influencer report that only contains influencer numbers cannot answer the question the finance team is actually asking, which is whether this money would do more somewhere else. Every metric on this page needs a comparator from outside the channel: your blended CAC, your paid social CPM, your studio's cost per asset. Augmentum Media builds reporting that way deliberately, because a programme that looks excellent in isolation and mediocre against paid search is a programme about to be cut.

The second error is reporting the flattering version of a real number. CAC excluding fees, EMV without cost, trackable revenue presented as total revenue. None of these are lies and all of them erode trust the first time someone checks. The honest version is more persuasive anyway, because a programme delivering customers at under £13.96 including everything does not need help.

Frequently asked questions

What are the most important influencer marketing KPIs?

Cost per thousand impressions, cost per acquired customer including all fees, return on ad spend against trackable links and codes, and the share of seeded creators who convert into affiliates. Those four cover cost, efficiency, return and whether the programme compounds. Everything else is context.

What is a good CPM for influencer marketing?

It depends entirely on whether you are earning the reach or buying it. Verified Augmentum figures range from £2.49 on a seeded nano and micro programme to £16.34 on a mid-tier paid campaign. The useful test is the ratio against your paid social CPM rather than any absolute number.

What is a good engagement rate for influencer marketing?

A less useful question than it appears, because engagement rate rises as audience size falls and therefore cannot compare creators of different sizes. As one reference point, a mid-tier paid campaign delivered 5.3% average engagement against a commonly cited 1.5 to 2% benchmark. Use it to spot dead or fake audiences, not to choose between tiers.

How do you calculate influencer marketing ROI?

Attributed revenue minus total programme cost, divided by total programme cost. The difficulty is never the formula, it is what goes into the cost side: product at landed cost, shipping, platform or agency fees and internal time all belong there. The full method is in our ROI post.

What is the difference between reach and impressions?

Reach counts separate accounts that saw the content. Impressions count total times it was served, so one person seeing a post three times is one reach and three impressions. Calculate CPM on impressions, and be careful comparing to a platform that reports the other one.

Should you report earned media value to your board?

Only next to what the programme cost. EMV on its own can be inflated by choosing a generous equivalent paid rate, and boards that have been shown a large EMV figure once tend to discount every number that follows it. Reported as a pair with cost, it is a fair way to value reach you did not pay for.

How do you measure influencer marketing without trackable links?

Add one question at checkout asking where the customer heard about you, with the creator programme as a named option. It is the cheapest attribution upgrade available to a DTC brand and it is the only one that sees the untracked majority of creator-driven demand.

How long before influencer KPIs become meaningful?

Content volume and CPM inside a month. ROAS and CAC after about a quarter, once a sales cycle has passed since the last post. Seed-to-affiliate rate after two quarters, because it depends on relationships forming. Judging a programme on month-one numbers mostly measures your shipping speed.

What is cost per creative and why does it matter?

Total programme cost divided by the number of usable content assets produced. It matters when creator content goes into your ad account, because it converts the programme from a marketing cost into a production saving. One Augmentum programme produced 15 or more VIP creatives a month at under £90 per video, alongside a 55% reduction in creative testing costs.

How many KPIs should an influencer report contain?

Six on the front page, with the rest available if asked. Reports that carry twelve headline metrics are usually compensating for not knowing which four matter, and they invite the reader to pick whichever number supports the view they already held.

What benchmarks exist for influencer marketing?

Very few trustworthy ones. Most published benchmarks are self-reported survey data from brands unlike yours, aggregated by companies selling software. That is why the figures on this page are all traceable to named Augmentum campaigns rather than presented as industry averages, and why we do not publish an industry average at all.

What is a good ROAS for an influencer programme?

Above your blended paid social ROAS, at a comparable scale, with fees included on both sides. As reference points, verified programmes have run at 5.12x and 5.41x. A first-quarter programme running below 1x is normal and not yet evidence of anything.

Sources

• Sprout Social, influencer marketing KPIs

• Meltwater, influencer marketing measurement

If any of this is useful, the fastest way to apply it is to have someone hold your current reporting against these numbers. Let's talk.