How UK Brands Can Choose the Right Influencer Marketing Agency
Not all influencer agencies are built the same. Here’s how to find one that actually delivers results, and the questions you should be asking before you sign anything.
The influencer marketing industry in the UK has matured rapidly over the past two years. What used to be a Wild West of DM-based deals and vague “brand awareness” metrics has evolved into a performance-driven channel that, done well, delivers measurable ROI. But that maturity also means the agency landscape has become crowded, and the gap between a great influencer marketing agency and a mediocre one has never been wider.
Whether you’re running your first influencer campaign or looking to switch agencies, this guide will help you understand what to look for, what to ask, and what should set off alarm bells.
What Does an Influencer Marketing Agency Actually Do?
Before you start evaluating agencies, it helps to understand the full scope of what they should be handling. A good influencer agency doesn’t just “find influencers”. They manage the entire lifecycle of creator partnerships.
That includes strategy development (defining who you should work with and why), creator identification and vetting, understanding the difference between creators, influencers, and affiliates, outreach and negotiation, briefing and creative direction, content approval workflows, campaign management, performance reporting, and ongoing relationship management with your creator roster.
Some agencies also handle paid amplification of influencer content, taking the best-performing organic posts and running them as paid ads. On TikTok, this is done through Spark Ads, which let you boost a creator’s post directly from their account, preserving all the social proof.
| Brands that repurpose top-performing influencer content as paid ads see an average 2.4x improvement in ROAS compared to brand-created ad creative alone. |
Seven Questions to Ask Any Influencer Agency
1. How do you find and vet creators?
The best agencies combine platform data with manual research. They should be able to explain their vetting process: how they check for fake followers, assess audience demographics, evaluate content quality, and verify brand safety. Ask for specifics, not generalities.
2. What does your reporting look like?
Ask to see a sample report from a previous campaign (anonymised, of course). You want to see more than just reach and impressions. Good agencies report on engagement rate, click-through rate, cost per engagement, conversion data (where trackable), audience sentiment, and, crucially, learnings and recommendations for future campaigns.
3. How do you handle creator relationships?
Long-term creator relationships produce better content than one-off transactional deals. Ask whether the agency maintains ongoing relationships with creators or starts from scratch each campaign. The answer tells you a lot about their operational maturity.
4. What’s your experience with my industry?
Influencer marketing for a beauty brand looks very different from influencer marketing for a B2B SaaS company. Some agencies specialise in specific verticals; others are generalists. Neither is inherently better, but they should be able to demonstrate relevant experience.
5. How do you structure pricing?
Agency pricing models vary widely. Some charge a percentage of influencer spend, others work on retainer or project fees, and some blend both. There’s no single right model, but you need transparency on what’s included. Ask specifically whether creator fees are included in the agency fee or billed separately.
6. What platforms do you specialise in?
An agency that claims to be equally expert across TikTok, Instagram, YouTube, Twitch, and LinkedIn is probably not deeply expert on any of them. Each platform has its own creator ecosystem, content formats, and best practices. TikTok influencer campaigns, for example, require a fundamentally different approach to Instagram because the TikTok algorithm rewards content quality over follower count.
7. Can you share case studies with measurable results?
Vanity metrics are easy to generate. Ask for case studies that show business outcomes: sales, sign-ups, app downloads, or qualified leads. If an agency can only show you “impressions” and “reach,” dig deeper.
Agency Models: Which Is Right for You?
Full-Service Influencer Agencies
Handle everything end-to-end. Best for brands that want to outsource influencer marketing entirely and don’t have in-house expertise. The Nonsensical approach sits here. We manage strategy through to execution so brands can focus on their core business.
Talent Management Agencies
Represent creators rather than brands. They can help you access specific talent, but their incentive is to maximise creator earnings, not your ROI. Useful for one-off celebrity partnerships, less suited to ongoing programmes.
Platform-Led Solutions
Tools like TikTok Creator Marketplace let you find and manage creators directly. Cost-effective but time-intensive. Works best for brands with internal teams who have the capacity to manage relationships.
Hybrid Approaches
Some brands use an agency for strategy and high-value partnerships while running smaller-scale affiliate programmes in-house. This can work well, particularly if you’re active on TikTok Shop where the affiliate model handles much of the creator relationship at scale.
What to Expect to Pay
Agency management fees typically range from 15-30% of total influencer spend, or £2,000 to £10,000+ per month on retainer depending on scope. Smaller campaigns might work on a project basis at £3,000 to £15,000 per campaign.
Creator fees vary enormously. Nano-influencers (1K-10K followers) might work for product alone or £50-£200 per post. Micro-influencers (10K-100K) typically charge £200-£1,500. Mid-tier (100K-500K) ranges from £1,500-£10,000. Macro-influencers and celebrities start at £10,000+.
For brands with smaller budgets, our guide to TikTok marketing for small businesses covers how to get started with influencer partnerships without a large upfront investment.
| The most cost-effective influencer strategy for most UK brands in 2026 is a network of 15-30 micro-influencers rather than one or two big names. Micro-influencers deliver 60% higher engagement rates on average. |
Red Flags to Watch For
Guaranteed virality. No agency can guarantee that content will go viral. If they’re promising specific view counts, they’re either naive or dishonest.
No clear measurement framework. If an agency can’t articulate how they’ll measure success before a campaign starts, they won’t be able to demonstrate ROI after it ends.
Reluctance to share creator lists. You should know who’s representing your brand. Agencies that won’t share their proposed creator roster before you commit are a red flag.
One-size-fits-all briefs. Every creator has a different style. Agencies that send identical briefs to every influencer will produce generic, underperforming content.
No paid strategy. The best influencer content often performs even better when amplified through paid. An agency that doesn’t integrate with your paid social strategy is leaving performance on the table.
How to Run a Successful Agency Pitch Process
If you’re formally reviewing agencies, keep the process tight. Invite 3-4 agencies maximum. Provide a clear brief that includes your objectives, budget range, target audience, and timeline. Ask for strategic recommendations, not spec creative.
Allow 2-3 weeks for responses. Schedule 45-minute presentations. Evaluate on strategic thinking, relevant experience, team quality, and cultural fit.
Check references. Ask to speak with a current client and, if possible, a former client. The former client conversation is often more revealing.
Working With Your Agency for Best Results
Once you’ve chosen an agency, the relationship works best when you treat them as a partner rather than a vendor. Share your broader marketing calendar so they can align influencer activity with other campaigns. Give them access to your analytics so they can optimise based on real conversion data.
For deeper thinking on how influencer marketing fits into your broader TikTok approach, our webinar on mastering TikTok influencer partnerships with Semrush covers the strategic framework we use with our clients.
| Looking for an influencer marketing agency that specialises in TikTok?At Nonsensical, we’re a TikTok marketing agency that runs influencer programmes for brands across beauty, retail, food, finance, and more. From creator identification to campaign execution and reporting, we handle everything.Get in touch to discuss your influencer marketing strategy. |
Further Reading
The Difference Between Creators, Influencers, and Affiliates on TikTok
The Top 10 Global B2B Brands on TikTok (Insight Report)
Webinar: Mastering TikTok Influencer Partnerships (with Semrush)
About Nonsensical.
We’re a TikTok agency based in the UK who work across strategy, organic, influencer, paid and TikTok Shop.
You can find more TikTok insight from us in our Substack – The TikTok Sauce.
