Marketing Agency vs In-House Team: Should You Build, Buy or Borrow Marketing Resources?

As your business grows, there tends to be a point where marketing becomes too important – and too complicated – to simply fit around everything else.

Perhaps you have one Marketing Manager trying to cover strategy, content, social media, SEO, paid advertising, email and reporting. Maybe you’ve already started building an internal team, but increasingly find yourself needing expertise that doesn’t exist within it. Or perhaps you’re weighing up whether your next investment should be another permanent hire or external marketing support.

This is where the marketing agency vs in-house team debate usually begins.

But there’s a slight problem with the question: it assumes you only have two choices.

Increasingly, growing businesses are building marketing functions that combine permanent employees, an outsourced marketing team and specialist external support. Rather than asking “agency or in-house?”, the better question is:

What combination of people, skills and resources does our business actually need to achieve its objectives?

With over 20 years combined experience growing marketing teams in-house, in agencies and with clients, today we thought we’d share our take on the topic – so grab a brew, and get comfy..

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The difference between an in-house and outsourced marketing team

An in-house marketing team consists of people directly employed by your organisation. Depending on the size of the business, that could range from one Marketing Manager to a sizeable department containing specialists across brand, content, digital, data, performance and communications.

An outsourced marketing team provides some or all of that capability externally. Rather than employing each person individually, you work with an agency or marketing partner that provides the strategy, specialist expertise and/or delivery capacity you need.

There’s also a third option: marketing resource augmentation.

This is where external marketing specialists work alongside your existing employees to fill specific skills or capacity gaps. You aren’t replacing your internal team; you’re strengthening it.

That distinction matters because the right answer changes considerably depending on what marketing capability you already have.

A simpler way to think about it: Build, Buy or Borrow

When you’re deciding how to resource marketing, it can help to move away from the traditional “in-house or agency?” question altogether.

Instead, think about the capability you need in three ways:

• Build it: Recruit, develop and retain the capability within your own marketing team.
• Buy it: Access the capability through an outsourced marketing team or agency that takes responsibility for an agreed area of strategy or delivery.
• Borrow it: Bring in specialist expertise or additional capacity to complement your existing team through marketing resource augmentation.

None of these is inherently better than the others.

You might build the capabilities that are strategically important to own long-term, buy access to a broader team where maintaining that breadth internally doesn’t make commercial sense, and borrow specialist expertise for a particular challenge, growth period or skills gap.

In fact, a mature marketing function may be doing all three at the same time.

The important question is deciding which capabilities belong where.

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The case for building an in-house marketing team

Let’s start with Build. There are plenty of good reasons to bring marketing capability in-house.

Nobody is closer to your organisation than your own employees. An internal marketer lives and breathes your brand, speaks to colleagues across the business and can build an understanding of your customers, products and internal politics that naturally develops over time.

Internal teams can also react quickly. If your sales team spots an opportunity on Tuesday morning, your marketing colleague can potentially be discussing it with them before lunch.

For established businesses with enough consistent demand for particular skills, permanent recruitment can therefore make complete sense.

The challenge comes when businesses expect a relatively small internal team to cover the enormous breadth of modern marketing.

SEO alone can involve technical SEO, content, digital PR, keyword research, user experience and analytics. Add paid media, organic social, CRM, email, creative, brand, conversion optimisation, tracking and marketing strategy, and suddenly your supposedly “full-service” Marketing Manager needs a rather impressive collection of hats.

If we had a pound for every time we’ve heard “we’re looking for a bit of a unicorn” internally… well, we wouldn’t be running The Business Tea – put it that way.

The skills challenge is very real. Marketing Week’s 2025 Career & Salary Survey found 60.5% of more than 3,500 respondents identified marketing effectiveness as a skills gap within their organisation, while 56.9% identified performance marketing as a tactical skills gap.

Meanwhile, research published by the Chartered Institute of Marketing (CIM) in 2026 found 78% of marketers believed workload was the main barrier preventing them from developing new skills.

The problem isn’t necessarily the quality of your people. Sometimes there simply aren’t enough hours – or enough specialist knowledge – within the team.

The cost of an in-house hire goes beyond salary

There is another consideration that can easily get overlooked when comparing an in-house hire with outsourced marketing support: salary isn’t the same thing as cost to the business.

Let’s say you’re deciding between recruiting another specialist and investing the equivalent budget with an external partner.

Putting a £50,000 salary next to a £50,000 annual agency retainer isn’t really a like-for-like comparison.

Depending on your organisation, an employee may also create costs associated with:

• employer National Insurance contributions;
• pension contributions and employee benefits;
• recruitment fees or internal recruitment resource;
• the time spent by managers interviewing candidates;
• onboarding and training;
• laptops, phones and other equipment;
• software licences and specialist marketing tools;
• management and professional development;
• annual leave and other periods where capacity isn’t available.

Not every one of those costs will apply equally to every business, of course. Nor does their existence make recruitment a bad investment. Far from it.

The important point is to compare the total cost of capability, rather than salary versus agency fee.

There’s also an opportunity cost that’s harder to put into a spreadsheet: time to capability.

A permanent hire usually requires you to write the role, secure budget approval, advertise or appoint a recruiter, shortlist, interview, negotiate notice periods and onboard the successful candidate. They then need time to understand your business before operating at full effectiveness.

That investment can be absolutely worthwhile if you’re building capability you’ll need for years.

But what if the commercial opportunity exists now?

If you’re entering a new market, rebuilding your website, fixing declining organic visibility or trying to scale paid acquisition ahead of a key trading period, waiting several months to build the capability internally may itself have a cost.

That’s why we’d encourage marketing leaders to consider three separate questions:

1. What will this resource cost us?
2. How long will it take before we have the capability?
3. How consistently will we need that capability once we have it?

Those questions can lead to very different answers.

Utilisation matters, too

This is one of the most overlooked parts of the in-house versus outsourced marketing conversation. 

You might need a brilliant technical SEO specialist. But do you need one for 37.5 hours every week?

Likewise, you may need senior strategic input, advanced analytics support or specialist paid media expertise – but perhaps only for a proportion of the month.

That creates an important distinction between needing access to a skill and needing to employ that skill full-time.

If there is enough meaningful, ongoing work to utilise a specialist properly, bringing that capability in-house can make excellent commercial sense.

If there isn’t, marketing resource augmentation can allow you to access specialist expertise without designing an entire permanent role around a part-time requirement.

And the opposite is equally true.

If you’re paying an external partner month after month for something that requires constant day-to-day involvement and could comfortably occupy a permanent employee, it’s reasonable to ask whether that capability should eventually move in-house.

The right operating model shouldn’t be ideological. It should change as the needs of the business change.

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When outsourced digital marketing makes sense

Then there’s Buy: accessing specialist capability through an outsourced digital marketing partner.

Outsourced digital marketing becomes particularly useful when the breadth of expertise required is greater than the team it makes commercial sense to employ permanently.

Imagine you need expertise across:

• marketing strategy
• SEO
• paid search and paid social
• content
• social media
• analytics and tracking
• conversion optimisation

Recruiting an experienced specialist for every discipline could mean building an entire department.

An external marketing partner can instead give you access to several areas of expertise through one relationship, scaling the level of support as your requirements change.

That’s one of the reasons we don’t believe outsourcing should automatically be seen as a stepping stone until you can “afford” an internal team. For some organisations, it is simply a more appropriate operating model.

It can also provide something that’s difficult to manufacture internally: outside perspective.

When you work within the same business every day, assumptions naturally form. An external team can challenge those assumptions, bring experience from other organisations and spot opportunities or problems that have become part of the furniture internally.

However, outsourced marketing isn’t automatically better.

Outsourcing has its own hidden costs

It’s also worth applying the same scrutiny to an agency relationship.

An agency retainer might look wonderfully simple on a budget line, but outsourcing doesn’t remove the need for internal resource.

Someone still needs to brief the agency, provide access to information, approve work, connect them with relevant stakeholders and make decisions.

If your Marketing Director spends hours every week correcting briefs, chasing account managers and translating recommendations back into the business, that’s a cost too.

Then there’s the question of knowledge.

An internal employee naturally accumulates organisational knowledge over time. An external partner needs access to that context – and if the relationship ends, you need to know that strategies, accounts, data, documentation and intellectual property don’t disappear with them.

Before outsourcing, we’d therefore look beyond the headline retainer and ask:

• Who will own the relationship internally?
• How much internal management will the partner require?
• Who owns the advertising accounts, analytics properties and marketing data?
• How will knowledge and decisions be documented?
• Are you paying for senior expertise but receiving predominantly junior delivery?
• What happens if you need significantly more – or less – resource next quarter?
• How easily could another partner or your internal team take over the work?

Good outsourcing should reduce pressure on your organisation, not simply relocate it.

And perhaps most importantly, you can’t outsource accountability altogether.

An external partner can own deliverables, channels and even substantial elements of strategy. But somebody needs to connect marketing with the wider commercial direction of the business.

That’s why outsourced marketing tends to work best when the relationship between internal and external teams is clear from the outset.

A poor agency relationship can leave you managing yet another supplier, waiting days for responses and receiving beautiful reports that don’t tell you whether marketing is actually helping the business grow.

The quality of the partnership matters considerably more than whether the people delivering the work appear on your payroll.

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Marketing resource augmentation: strengthening the team you already have

Finally, there’s Borrow – although we’re not talking about borrowing someone’s Marketing Manager every other Tuesday. This is where marketing resource augmentation comes in and where we think the agency vs in-house conversation gets much more interesting.

Marketing resource augmentation allows a business to retain its internal knowledge and capability while bringing in external expertise where it’s genuinely needed.

Let’s say you have a Marketing Director, Marketing Manager and Content Executive.

They understand the business. They own the strategy. They’re doing good work.

But you’re planning aggressive organic growth and nobody in the team has advanced technical SEO expertise.

You don’t necessarily need to outsource your entire marketing department. Equally, recruiting a full-time technical SEO specialist might not be justified.

You can augment the existing team with that expertise.

The same principle might apply if you need additional paid media resource, analytics expertise, senior strategic input or simply more hands during a major launch.

For larger organisations, external partners can also provide additional capacity during particularly demanding periods without permanently increasing headcount.

In-house vs outsourced marketing vs resource augmentation

So, which structure makes sense?

Consideration	In-house Team	Outsourced Marketing Team	Marketing Resource Augmentation
Upfront commitment	Higher – recruitment, onboarding and employment commitment	Usually lower – agreed contract or retainer	Flexible – resource added around existing team
Speed to capability	Usually slower due to recruitment and onboarding	Potentially fast if the right partner is appointed	Potentially fast for clearly identified skill gaps
Business knowledge	Typically strongest over time	Requires effective onboarding and integration	Internal knowledge remains in-house while specialists add expertise
Breadth of expertise	Depends on team size and budget	Can provide access to multiple specialists	Adds specific expertise where internal capability is limited
Specialist utilisation	Best when there’s enough ongoing work to justify the role	Resource can often flex across disciplines	Particularly useful when expertise is needed part-time
Day-to-day availability	High	Depends on service model and contract	Internal team remains available; specialists support agreed areas
Management requirement	Requires line management, development and performance management	Requires supplier/relationship management	Requires coordination between internal and external teams
Tools and technology	Business usually funds required platforms and licences	Some specialist tools may be included, but not always	Often a combination of internal and partner technology
Scalability	Additional capacity normally requires recruitment	Resource can potentially scale faster	Designed to expand or contract around requirements
Knowledge retention	Knowledge remains within the organisation, subject to employee turnover	Documentation and handover become particularly important	Core organisational knowledge stays internally
Control	High direct control over priorities and workload	Governed by scope, retainer and ways of working	High internal ownership with external specialist input
Cost structure	Salary plus employment, recruitment, equipment, technology and management costs	Retainer/project fees plus internal relationship-management time	Cost concentrated around additional capability required
Best suited to	Consistent, long-term requirements that justify dedicated headcount	Organisations needing broader capability or external delivery	Established teams with identifiable capacity or specialist skill gaps

And that’s really the point: there isn’t a universally correct model. The important word in this table is “typically”. A brilliant agency may know your business better than a recently recruited employee. An experienced internal team can have broader expertise than a small agency. And an outsourced relationship can sometimes be harder to scale than recruitment.

These aren’t rules. They’re factors to investigate when designing your marketing operating model.

Research from Gartner reflects this increasingly nuanced approach to marketing operating models, with its research examining how organisations combine different internal service structures and agency partners according to the type of work being performed.

Meanwhile, Gartner’s 2025 CMO Spend Survey found marketing budgets remained at 7.7% of company revenue, with marketing leaders under continued pressure to improve productivity and demonstrate value.

When budgets are being scrutinised, the question isn’t simply whether outsourcing or employing someone is cheaper.

It’s whether your marketing structure gives you the right capability to deliver the commercial outcome you’re investing in.

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How to decide whether to outsource or hire in-house

Before opening another job vacancy – or sending an agency a brief – we’d recommend pondering these seven points:

1. Start with the business objective, not the resource.

“We need another marketer” isn’t really a requirement. What needs to change commercially? Entering a market? Increasing pipeline? Reducing acquisition cost? Building brand awareness? Fixing measurement? Once the outcome is clear, work backwards into capability.

2. Audit capability and capacity separately.

Ask: Could our team do this if they had more time? If yes, it’s a capacity problem.
Do we have the expertise to do it at the required level? If no, it’s a capability problem. The solutions may be completely different.

3. Model the total cost – not salary versus retainer.

Build an actual 12 – 24 month comparison. For employment: salary + employer costs + recruitment + equipment + software + training + management. For outsourcing: fees + additional tools/media + internal management time + onboarding/transition costs. Compare the cost of achieving the required capability, not two invoice values.

It may be that external support makes sense in the short term while you recruit permanent capability. Equally, you might decide that a fractional or augmented model makes more commercial sense long-term. It depends on the requirement, your budget and your objectives.

4. Consider utilisation.

How many hours of advanced SEO, analytics, paid media, strategy etc. do you actually need? This is where a role that sounds sensible on an organisational chart can look very different commercially.

5. Factor in speed and the cost of waiting.

Recruitment might ultimately be cheaper, but if it takes four months and delays a commercially important initiative by four months, that delay belongs in the decision too. Conversely, if there’s no urgency, paying a premium for immediate external access may make less sense.

6. Decide what knowledge and ownership should live inside the business.

Some capabilities may be strategically important enough that you deliberately want to own them. Brand knowledge, customer understanding, commercial strategy and stakeholder relationships may fall into this category. That doesn’t mean every executional specialist must sit internally.

There’s a risk consideration here too. If a capability is commercially critical, ask what would happen if the person responsible left – whether they’re an employee or an external partner. Avoid creating single points of failure. Documentation, shared access, cross-training and clear ownership matter regardless of which resourcing model you choose.

7. Ask how reversible the decision needs to be.

This is a big one. Permanent headcount is deliberately a longer-term commitment. Outsourced resource is usually more variable. If your strategy, demand or budget is uncertain, flexibility matters. If the need is stable and strategic, permanence may be preferable.

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What could Build, Buy or Borrow look like in practice?

Let’s make this a little less theoretical. Imagine you’re a Marketing Director at a growing business. You already have a small internal team consisting of yourself, a Marketing Manager and a Content Executive. 

You’ve secured an additional £120,000 marketing resource budget for the next 12 months. For illustration, we’ll use that figure to show how the same budget could be approached in very different ways.

You’ve identified several things that need to happen. Organic search needs more strategic and technical attention. Paid media needs to scale. Your measurement isn’t as reliable as you’d like. The Content Executive is already close to capacity. And, as Marketing Director, you’re spending more time getting campaigns out of the door than you are thinking about the bigger commercial picture.

There are several ways you could approach it.

Option 1: Build – recruit the capability in-house

You could use the budget to recruit one or two permanent employees.

Perhaps that’s a Performance Marketing Manager and an SEO Manager, depending on salaries, employer costs and your wider employment package.

If you’ve got enough ongoing work to utilise those roles properly, that could be an excellent investment. You’re building knowledge inside the organisation, creating dedicated capacity and developing a team around capabilities you expect to need for years.

But you’d also need to consider what the £120,000 really needs to cover.

It’s not simply two advertised salaries. There may be employer contributions, recruitment, equipment, software, training and management costs to account for. You’ll also need to consider how quickly you can recruit both people and whether those two hires solve the full problem.

For example, who fixes your analytics implementation if neither specialist has that expertise?

Option 2: Buy – appoint an outsourced marketing team

Alternatively, you could invest some or all of that £120,000 with an external marketing partner.

Instead of recruiting two defined roles, you might gain access to expertise across SEO, paid media, analytics, strategy and other disciplines as they’re required.

That breadth can be particularly useful when the problem doesn’t neatly fit into one or two job descriptions.

You may also be able to access that capability faster than you could recruit it.

But you’re making a different trade-off.

The expertise isn’t permanently embedded within your organisation. You’ll need effective briefing, communication and knowledge transfer, and someone internally still needs to own the commercial direction of marketing.

If you actually need two people embedded in the business five days a week, an outsourced model may not be the most sensible long-term answer either.

Option 3: Borrow – augment the team you already have

Or perhaps the answer is neither of those. You might conclude that your biggest permanent need is additional day-to-day capacity and recruit another Marketing Manager internally.

You then use the remaining budget to augment that team with specialist SEO, paid media, analytics or strategic expertise.

Now you’re deliberately mixing models.

Your permanent team retains business knowledge, stakeholder relationships and day-to-day ownership. External specialists provide deeper expertise where you don’t have enough demand to justify several additional full-time roles.

Over time, one of those external capabilities might become important enough to bring in-house. And that’s completely fine.

Option 4: Build, Buy and Borrow

There’s another possibility: you do all three.

• You build core marketing capability internally.
• You buy ongoing support in an area where you need broader delivery.
• And you borrow highly specialist expertise for specific projects or periods of increased demand.

That’s why we’d be wary of trying to find the universally “best” model.

Even with the same £120,000 budget, two businesses could make completely different resourcing decisions – and both could be right.

A business with a major paid media operation might have enough ongoing demand to justify bringing performance marketing in-house. Another business might barely run paid media but have significant organic search opportunities, so its ideal structure looks completely different.

The budget doesn’t determine the operating model. Your objectives, existing capability, utilisation requirements, urgency and long-term strategy do.

The useful conversation therefore isn’t: “How many people can we hire for £120,000?” or “What can an agency give us for £120,000?”… it’s “What combination of capability gives us the best chance of achieving what the business needs to achieve?”

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Your marketing operating model doesn’t have to be permanent

And here’s the other important thing to remember: the answer you arrive at today doesn’t have to be the answer forever.

Businesses often approach the decision as though they’re choosing their marketing structure for the next decade. You’re not.

Your balance of Build, Buy and Borrow can – and probably should – change as your organisation grows.

A business might initially outsource most of its marketing because it needs broad capability but doesn’t yet have the scale to build a department.

As it grows, it might recruit a Marketing Director internally while retaining external specialists.

Later, paid media might become strategically important and substantial enough to justify an internal Performance Marketing Manager. SEO may remain externally supported because the business only requires specialist technical input periodically.

Then a major international expansion might temporarily require additional agency resource again.

Your marketing operating model should evolve with the business.

That means the question isn’t simply “Should we outsource marketing?”. It might be:

“What should we own now? What should we access externally? And what capability are we deliberately building towards?”

That brings us back to marketing resource augmentation.

For established marketing teams in particular, the most effective answer may not be replacing internal resource or handing everything to an agency. It may be creating a strong internal core and deliberately surrounding it with specialist expertise that can expand and contract as priorities change.

Build what makes sense to own. Buy what makes sense to outsource. Borrow the expertise you need when you need it.

And keep reviewing that balance as the business evolves.

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What should you expect from an outsourced marketing team?

There’s one final point worth making. Choosing external marketing support shouldn’t mean accepting a distant supplier relationship.

A strong outsourced marketing team should understand your objectives, know what’s happening elsewhere in the business, work comfortably alongside internal stakeholders and be prepared to challenge your thinking when necessary.

That’s how we approach it at The Business Tea.

We can operate as a broader outsourced marketing function, provide fractional marketing leadership or work alongside established marketing departments to add specialist capability where it’s needed.

The objective isn’t to replace good internal marketers. It’s to build the marketing resource your business actually needs.

Because as your organisation grows, the answer probably isn’t “agency or in-house?”. It might be a bit of both.

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