The UK Guide To Hiring A Paid Ads Agency

I see this question a lot. The UK is flooded with paid advertising agencies, and frankly, a lot of them are cowboys. They talk a good game, flash some impressive-looking slides, and then underdeliver, leaving you with a lighter wallet and a deep-seated mistrust of the entire industry. It’s a proper minefield, and it's easy to get burned.

The problem is most businesses don't know how to hire an agency. They ask the wrong questions, look at the wrong things, and get dazzled by vanity metrics. The goal isn't to find the cheapest quote or the slickest salesperson. The goal is to find a partner who can become a genuine profit centre for your business. Someone with the expertese to turn your ad spend into predictable, scalable revenue. This isn't about finding a supplier; it's about hiring a specialist.

So, let's cut through the noise. Here is my no-nonsense guide to finding and hiring a paid ads agency in the UK that actually knows what they're doing. No fluff, just the stuff that actually matters, based on years of being on both sides of the table.

They all sound great on a sales call. How do I know who's actually good?

This is the first hurdle, and it's where most people fall. A good sales process doesn't equal a good service delivery. You need to look past the pitch and demand hard evidence. For me, it boils down to one thing above all else: case studies.

Not just a logo on a page. I'm talking about detailed, in-depth breakdowns of past work. Here's what you should be looking for:

-> Niche Relevance: Have they worked with businesses like yours? An agency that gets amazing results for e-commerce brands selling women's apparel might be completely lost when it comes to generating leads for a B2B SaaS company in the London FinTech scene. The strategies are worlds apart. For instance, we've driven a 691% return for an apparel brand, but the approach we used there—heavy on Meta and Pinterest visual ads—would be useless for the B2B software client we got a $22 CPL for on LinkedIn. Look for proof they understand your world.

-> Tangible, UK-Focused Results: Are they showing you real business metrics? I don't care about impressions or clicks. I want to see revenue generated (in £), Return on Ad Spend (ROAS), Cost Per Acquisition (CPA), and number of qualified leads. If their case studies are full of fluffy metrics, it's because the real ones aren't impressive. We have a case study showing how we generated £107k in revenue for a client from prize draws. That's a real number. That's what you're looking for.

-> The "Why", Not Just the "What": A great case study tells a story. It should explain the initial problem, the strategy they developed, the hurdles they overcame, and *why* it worked. If it just says "We increased ROAS by 200%", that's lazy. It tells you nothing about their thought process.

Now, a slightly controversial point. Stop asking for client references.

Tbh if a potential client asks us for references after we've shown them detailed case studies and offered them a free strategy review, it's an instant red flag. It tells us there's a fundamental lack of trust from the outset, and that's not a foundation for a good partnership. Any decent agency values and protects their clients' time. Their work, case studies, and public reviews should be enough to build that initial trust. If it's not, you're probably not a good fit for each other.

What should I ask on the first call?

Your first interaction with a potential agency should not be a sales pitch. It should be a consultation. The single most important thing you can do is see how they think. The best way to do that is to get them to audit your business in real-time.

Forget "request a demo." The only demo that matters is them demonstrating their expertise on *your* specific problem. We offer a free initial consultation where we'll literally open up a client's ad account with them on a screen share and point out opportunities and problems. That's the bar.

During this call, pay attention to the questions they ask *you*.

• A bad agency will talk about themselves.
• A good agency will ask about your business: What are your profit margins? What's your customer lifetime value? What's your sales cycle? Who is your absolute ideal customer?

They should be trying to understand your business model before they even think about suggesting a solution. If they jump straight to "Oh, you need Google Ads" or "We'll run some Facebook campaigns" without understanding the fundamentals, they're just selling a cookie-cutter service. Run away.

Here's a simple flowchart to help you visualise the vetting process. If you get a "No" at any stage, you save yourself a lot of time and money by walking away.

How much should I be spending and what results can I expect?

This is the million-dollar question, or rather, the million-pound question. And the answer most businesses get wrong is by focusing on the wrong metric. They obsess over Cost Per Lead (CPL) or Cost Per Click (CPC). "How low can you get my CPL?" is a question that instantly tells an experienced practitioner that the client is thinking about the problem incorrectly.

A cheap lead is often a worthless lead. The real question is not "How low can my CPL go?" but "How high a CPL can I afford to acquire a fantastic customer?" The answer to *that* question is found in your Customer Lifetime Value (LTV).

Your LTV is the total profit you can expect to make from a single customer over the entire course of your relationship. Once you know this number, you can make intelligent decisions about your advertising budget. Here's how to calculate it:

Once you have your LTV, a healthy rule of thumb is a 3:1 LTV to Customer Acquisition Cost (CAC) ratio. So, if your LTV is £10,000, you can afford to spend up to £3,333 to acquire a new customer and still have a very healthy business. Suddenly that £50 lead from Google Ads or £100 lead from LinkedIn doesn't seem so expensive, does it? It looks like an absolute bargain. This is the maths that unlocks aggressive, intelligent growth.

As for what to expect, it varies wildly. We've managed campaigns for childcare services where the CPL was around £10, and for a home cleaning company we got it down to £5 per lead. On the other hand, for a client in a competitive HVAC market, leads were closer to $60 (£47). For B2B software, we’ve seen CPLs of $22 (£17) on LinkedIn for high-value decision-makers. It all depends on the market, the platform, and the offer. A good agency will give you a realistic range based on their experience, not a wild promise.

But don't I need to build my brand first?

Here’s an uncomfortable truth about paid advertising, especially on platforms like Meta (Facebook & Instagram). When you set your campaign objective to "Brand Awareness" or "Reach," you're telling the algorithm to "find me the cheapest possible eyeballs".

And the algorithm is very good at its job. It will seek out users who are notorious for scrolling endlessly but never clicking, never engaging, and definatly never buying anything. Why? Because their attention is cheap. Nobody else is bidding for it. You are effectively paying the world's most powerful advertising machine to find you the worst possible audience for your product.

For a startup or SME, this is suicide. You don't have the budget of Coca-Cola to burn on passive branding. The best form of brand awareness for you is a customer switching to your product and raving about it. That only happens through conversion.

Awareness is a byproduct of having a great product that solves a real problem, not a prerequisite for making a sale. That's why, 99% of the time, you should be running campaigns that optimise for a conversion: a sale, a lead, a trial sign-up, an appointment. Let the platform's AI work for you to find people who actually take action, not just people who look.

What are the biggest red flags to watch out for?

Navigating the agency world is tricky, but there are some clear warning signs that should have you heading for the hills. If you spot any of these, proceed with extreme caution, or better yet, just end the conversation.

• Guarantees and Promises: This is the biggest one. Tbh in paid advertising, you can't really promise anything. There are too many variables: market changes, competitor actions, platform algorithm updates. Anyone who guarantees you a specific ROAS or a fixed number of leads is either lying to get your signature or dangerously inexperienced. Real proffesionals talk in terms of realistic targets and data-driven projections.
• A Jargon-Heavy Pitch: If a call is filled with words like "synergy," "leverage," "growth hacking," and "game-changer," it's a massive red flag. Experts have the confidence to speak plainly and clearly. Jargon is often used to mask a lack of real substance.
• A One-Size-Fits-All Strategy: If an agency recommends a specific ad platform before they've even asked about your ideal customer, they're not selling a strategy, they're selling a product. We've had B2B clients who were told they *must* be on Facebook, when their audience of senior decision-makers was almost exclusively active on LinkedIn. The platform follows the audience, not the other way around.
• Fixation on Vanity Metrics: Be wary of agencies that lead their reports with 'Impressions', 'Reach', or 'Clicks'. While these have a place, they don't pay the bills. The reports and conversations should be centred around what actually moves the needle for your business: Cost Per Acquisition, Revenue, and ROAS.
• The "Black Box" Approach: Does the agency refuse to give you admin access to your own ad accounts? Do they get cagey when you ask what specific tests they're running? This is a huge red flag. It's your money and your business data. You should have full transparency and ownership. A good agency acts as a partner, not a gatekeeper.

Okay, I've hired someone. What happens next?

Signing the contract is the start, not the end, of the process. The first 90 days are critical for setting the partnership up for success. It's not about immediate, massive returns; it's about building a foundation of data, testing, and learning.

The first month is all about setup and data collection. This involves a deep-dive kick-off call, a thorough audit of your tracking (like the Meta Pixel and Google Analytics), and launching the initial batch of campaigns. These first campaigns are designed to gather data, not necessarily to be wildly profitable from day one. You're testing audiences, creatives, and messaging to see what resonates.

The second and third months are about optimisation and scaling. Using the data from month one, the agency should be culling the campaigns that don't work and doubling down on the ones that do. This is where you should start to see performance stabilise and improve. Costs per lead should start to drop, and ROAS should climb.

This is a partnership. The agency needs your feedback. Are the leads they're generating actually any good? What are prospects saying on sales calls? This feedback loop is what allows a good agency to refine targeting and messaging to deliver not just more leads, but *better* leads.

I've detailed my main recommendations for what you should expect below:

Is an Agency Right For You?

Let's be brutally honest. Hiring a paid advertising agency isn't the right move for every business. If you have a very small budget (less than £1-2k per month in ad spend), it can be difficult for an agency to gather enough data to optimise effectively. If your product or service is brand new and you don't yet have a proven offer that people will pay for, ads will only accelerate your failure. You're better off validating your offer organically first.

However, if you have a business with a proven product, a clear understanding of your customer, and you're ready to invest in growth, the right agency can be the single best investment you make. They provide the expertise and the manpower to build a scalable customer acquisition machine, freeing you up to do what you do best: run your business.

The key is to approach the hiring process with a healthy dose of skepticism, a clear framework for evaluation, and a focus on business metrics, not advertising jargon. Don't be sold a dream; invest in a provable process.

If you're still not sure what your next steps should be, the best move is often just a straightforward, no-obligation chat. We offer a free consultation where we'll look at your business, your goals, and your current advertising (if you have any) and give you some honest, direct advice on what we'd do. There's no hard sell. Just a chance to see if our expertise is the right fit to help you grow.

Hope that helps!