What is influencer marketing? A brand pays a content creator, or sends them free product, so they present it to a community that already follows them. The message runs on the creator’s own account (Instagram, TikTok, YouTube or LinkedIn) in their own words. No media space is bought, which sets it apart from a classic ad.
What separates a collaboration from a classic ad
A traditional ad buys audience by volume. A collaboration borrows the one a creator has built around a precise subject: a perfumer has no business in the community of a fly-fishing account.
Influencer marketing also overlaps with other mechanisms. Gifting means sending a product with nothing in writing in return. Affiliation pays the creator for every sale made through their link. User-generated content (UGC) has customers or creators produce videos that the brand reuses in its own ads. A single campaign can combine all three.
Nano, micro or macro: choosing the size of the community
Nano-influencers, micro-influencers and macro-influencers are told apart by follower count. The thresholds change from one author to the next, so the table gives orders of magnitude only.
| Category | Followers (order of magnitude) | Common use case |
|---|---|---|
| Nano | 1,000 to 5,000 or 10,000 | Local niche, word-of-mouth recommendation |
| Micro | 10,000 to 100,000 | Topic-focused audience, targeted launch |
| Macro | Over 100,000 | Broad awareness, product announcement |
The larger the community, the higher the cost. A small business that sells in one region or in a B2B niche often gets a better fit between audience and message from smaller accounts.
Setting up a campaign in five steps
- Set the goal. Awareness, traffic to the site, sales or newsletter sign-ups: one main goal, and a measurable one.
- Describe the target: age, job, interests, and the platform where they spend their time.
- Select the creator. Check their engagement rate (interactions relative to audience) over their last 10 pieces of content, about 1 to 2 months of posts for an active account. Look for fake followers: a sudden spike in followers, generic comments, an audience spread across countries the brand does not ship to. Finally, check that their audience looks like your target.
- Write the brief: key message, mandatory mentions, format (post, Reel, story, video), publication dates, right to review. Leave room for the creator’s own way of speaking.
- Sign the contract, then follow the publication and measure.
Influencer platforms such as Kolsquare or Influee, and agencies, speed up the search for profiles. For a first test, a direct message to 5 creators is often enough. State in that message the format you expect (Instagram Reel, TikTok or YouTube video, LinkedIn post), the broadcast period and the existence of a contract that complies with French law no. 2023-451, to avoid back-and-forth.
What a collaboration costs
There is no official price list. The price depends on the platform, the format, exclusivity, the duration of usage rights and negotiation. As an order of magnitude, influencer software vendor Influee reported in March 2026 25 to 150 euros per post for an Instagram nano-influencer. According to Influee, a Reel costs 2 to 3 times more than a static post. These figures come from a player in the sector and have not been cross-checked: always ask for several quotes.
Payment can also take the form of a free product or an affiliate commission. The compensation is then written into the contract.
What the 2023 law requires of the brand and the creator
The French law no. 2023-451 of 9 June 2023 regulates the activity of commercial influencers in France. It targets people who use their reputation with their audience to promote goods or services in exchange for payment. Ordinance no. 2024-978 of 6 November 2024, in force since 8 November 2024, later amended the law, notably article 9 on influencers established outside the European Union.
- Under article 5-2, the content must carry the French wording « Publicité » (“Advertising”) or « Collaboration commerciale » (“Commercial collaboration”), or an equivalent mention suited to the medium, in a legible way. Article 5 also requires « Images retouchées » (“Retouched images”) when the body shape or face has been altered. The mention « Images virtuelles » (“Virtual images”) applies when they are AI-generated.
- A written contract is mandatory on pain of nullity, above the pay threshold set by decree (article 8, available on Légifrance). According to Légifrance, it states the identity of the parties, the assignments, the payment, the rights and obligations of each side and the application of French law.
- The advertiser, its agent if any, and the influencer are jointly liable for damage caused to third parties.
- An influencer based outside the EU, the EEA and Switzerland who targets the French public must appoint a representative in the Union in writing and take out civil liability insurance with an insurer established in the Union (article 9).
Penalties
The consolidated text on Légifrance sets three levels of penalty. Article 5, III punishes a missing “Retouched images” or “Virtual images” label with one year in prison and a 4,500 euro fine. A missing “Advertising” or “Commercial collaboration” label counts as a misleading commercial practice under article L. 121-3 of the French consumer code, and the law attaches no amount of its own to it. Finally, promoting products or practices that article 4 prohibits carries the penalties of article L. 132-2 of the consumer code, with a possible ban on carrying out the activity concerned. These penalties target the creator first. The brand stays exposed through the joint liability in article 8.
The ARPP certificate
The ARPP, France’s professional advertising regulation authority, offers creators the Responsible Commercial Influence Certificate, an online course whose final exam requires 75% correct answers. The law of 9 June 2023 does not mention this certificate. It is voluntary training. A brand can still ask for it as a guarantee before signing.
This list is no substitute for legal advice. For a campaign with a significant budget, have a lawyer review the contract. Also write the mention into the brief, so the creator places it in the content itself, for example in the caption of an Instagram post or as an overlay on a TikTok video.
Measuring what the campaign returns
Return on investment is calculated from the goal set in step 1. Four KPIs come up most often: engagement rate, traffic, attributed sales together with sign-ups, and cost per engagement (budget divided by the number of interactions obtained). Fictional example: 600 euros for 1,200 interactions gives 0.50 euro per engagement.
To attribute traffic, give each creator a distinct link with UTM tags, for example utm_source=instagram&utm_medium=influence&utm_campaign=creator-name-2026. In Google Analytics 4, these parameters show up in the traffic acquisition report. Add a promo code in their name. The two levers overlap: a buyer who did not click the link will still use the code.
This is also where email extends the campaign. A sign-up form for the newsletter tied to the creator’s link turns a spike of attention into a contact base you can use after the post is over, provided you collect the consent required by the GDPR. Addresses typed on a phone often contain typos: check them before the first send, because bounces weigh on sender reputation. The full tracking is then read in your marketing KPIs.
On the strategy side, influencer marketing belongs to inbound marketing: content draws the audience to the brand.
Frequently asked questions
Do you need a contract for a simple product shipment?
The law defines commercial influence as an activity carried out for payment. The case of a product alone, with no payment, is less clear: if you expect a post in return, write a contract anyway and get legal advice.
Which content format should you pick for a first test?
According to Influee, a Reel costs 2 to 3 times more than a static post. Start with a single format with two or three creators to compare results on an equal budget.
