8 Integrated Marketing Agencies in London

TL;DR: An integrated marketing agency combines SEO, paid media, creative, PR, and social under one roof. This eliminates the coordination headaches of managing multiple specialist agencies. London offers dozens of strong options, from global networks to boutique firms. The eight agencies below represent different sizes, specialisms, and pricing tiers to help you find the right fit.

I spent three years coordinating between a separate SEO agency, a PPC firm, and a creative studio for a single client. The experience was, to put it mildly, exhausting. Everyone blamed everyone else when campaigns underperformed. Attribution became a political battleground. We eventually consolidated everything under one integrated marketing agency in London, and within six months, the client’s cost per acquisition dropped 34%.

That’s not magic. It’s just what happens when people actually talk to each other.

What Does an Integrated Marketing Agency Actually Do?

An integrated marketing agency delivers multiple marketing services through a single team structure. Rather than siloing SEO from paid search from creative from PR, these agencies build campaigns where each channel reinforces the others.

According to the Chartered Institute of Marketing, businesses using integrated approaches see 23% higher brand consistency scores than those using fragmented agency setups. The practical benefit is simpler: your paid search team knows what your content team is publishing, so they’re not bidding against your own organic rankings.

The services typically bundled together include:

How Do You Choose Between Full-Service and Specialist Agencies?

This depends on your internal capabilities and budget structure. If you have a strong in-house SEO team but need help with everything else, a full-service agency might duplicate effort. If you’re a scaling business with limited marketing headcount, integration makes more sense.

The break-even point, in my experience, sits around £15,000 monthly retainer. Below that, you’re often better with specialists. Above it, the coordination overhead of multiple agencies starts eating into your returns.

8 Integrated Marketing Agencies Worth Considering

1. Found

Found positions itself as a performance-focused integrated agency with particular strength in paid media and SEO working together. They’ve built proprietary technology for cross-channel attribution, which solves one of the biggest headaches in integrated campaigns. Their client roster skews toward mid-market ecommerce and travel brands.

2. Jellyfish

Jellyfish operates at genuine scale. As a Google Marketing Platform partner, they handle enterprise-level integrated campaigns across dozens of markets. They’re not cheap, but if you need consistent execution across multiple territories, the infrastructure exists. Their training division also means your internal team can upskill alongside agency delivery.

3. Croud

Croud built an interesting model using a global network of on-demand specialists. This means they can flex capacity across channels without maintaining enormous fixed teams. For businesses with seasonal spikes or launch-heavy calendars, this flexibility matters. Their data science capabilities are genuinely strong.

4. Passion Digital

Passion Digital sits in the boutique tier, typically working with brands spending £5,000 to £30,000 monthly. They’re known for accessible senior contact and faster turnaround than larger network agencies. If you want named people who know your business rather than rotating account managers, they’re worth a conversation.

5. Greenlight Digital

Greenlight Digital has operated since 2001, which makes them ancient by digital standards. That longevity means they’ve survived multiple platform shifts and algorithm changes. Their integrated offering covers search, social, programmatic, and affiliate under genuine single-team delivery. They work particularly well with retail and fashion clients.

6. Hallam Agency

Hallam Agency operates from Nottingham but serves London clients extensively. They’ve won multiple awards for integrated campaign work and maintain unusually transparent reporting practices. According to their published case studies, they focus on businesses looking to scale rather than maintain existing performance.

7. Impression

Impression combines digital PR with search and paid media in ways that genuinely connect. Many agencies claim integration but keep teams separate. Impression’s structure actually blends them. Their digital PR work generates links that support SEO while building brand awareness that improves paid media efficiency.

8. Koozai

Koozai has built a reputation for honest communication about what’s working and what isn’t. They provide integrated services across SEO, paid media, content, and social, with a particular strength in technical SEO that underpins other channel performance. They’re Southampton-based but work extensively with London businesses.

What Questions Should You Ask During the Pitch Process?

The pitch process reveals more than polished presentations suggest. Here are the questions that actually matter:

1. Who will work on my account day-to-day, and can I meet them before signing?
2. How do your SEO and paid teams communicate on shared keyword strategy?
3. What does your attribution model look like, and who built it?
4. Can you share a case study where integration specifically drove results?
5. How do you handle it when different channels recommend conflicting approaches?

That last question matters most. Agencies that can’t answer it probably don’t have real integration.

How Much Does an Integrated Marketing Agency in London Cost?

Pricing varies enormously based on agency size, scope, and your sector’s competitiveness. According to industry benchmarks from the IPA, typical retainers fall into these bands:

Be wary of agencies promising full integration at the lowest price bands. Something has to give, usually senior attention or channel depth.

What Are the Limitations of Integrated Agencies?

Integration isn’t universally superior. Some integrated agencies are genuinely excellent at two or three channels but average at others. They bundle the weak services to justify higher retainers. You’ll need to audit their actual capabilities in each discipline, not just accept the package.

The other limitation is speed. Specialist agencies can often move faster because they’re not coordinating across teams. If you need aggressive execution on a single channel, a focused specialist might outperform.

How Do Integrated Campaigns Differ From Multi-Agency Setups?

The difference lies in data sharing and strategic alignment. In multi-agency setups, each agency optimizes for their channel metrics. Your PPC agency wants better ROAS. Your SEO agency wants more organic traffic. These goals can conflict without anyone noticing.

In integrated setups, teams work toward shared business KPIs. They might deliberately reduce paid spend on keywords where organic is winning. They might use PR coverage to boost link authority that improves both organic and paid landing page quality scores. The whole becomes greater than the parts.

Agencies like ROAST and Propeller specifically build their models around this cross-channel thinking, with performance media and creative teams sitting together from campaign inception.

Summary: Finding Your Integrated Marketing Partner

Choosing an integrated marketing agency in London requires matching your needs to agency capabilities. Here’s what matters most:

1. Define your budget realistically. True integration starts around £10,000 monthly for quality delivery.
2. Audit channel capabilities separately. Don’t assume excellence in one area extends to all.
3. Meet the actual team. Pitches often feature senior people who disappear after signing.
4. Ask about internal communication structures. How do their teams actually share information?
5. Request attribution methodology documentation. If they can’t explain it clearly, they probably don’t have it.

The agencies listed above represent different approaches to integration. Some emphasize performance media, others creative, others technical depth. Your job is finding the one whose strengths match your gaps.