When Is It Time to Bring in an Agency Instead of Doing Everything In-House?
Key Takeaways
Bring in support when capacity or specialist gaps repeatedly delay commercially important work.
Hand over a defined responsibility, with clear decisions and measures, rather than an unfiltered task list.
Compare the full cost of hiring, training and managing delivery before choosing an agency arrangement.
It is time to consider an agency when the work your business needs consistently exceeds what your team can deliver well. That might mean entering an unfamiliar channel, improving weak campaign performance or giving an overstretched team room to plan beyond next week's deadlines.
The decision does not require handing over the entire marketing function. One Day Agency's media planning and buying and creative services can support specific areas while your internal team retains ownership of the brand and business priorities. The task is to identify where outside expertise would make a meaningful difference.
Which Signs Suggest Your Team Needs Support?
A busy week is normal. A permanent backlog that prevents useful work is a different problem. Review the last few campaigns and look for repeated consequences, rather than relying on how stretched everyone feels.
Campaigns launch late because routine requests take priority over planned work.
One person handles a specialist channel without experienced cover or a second opinion.
Reporting describes activity, but nobody has time to investigate what should change.
Creative is resized repeatedly without testing new messages or addressing weak performance.
Senior marketers spend most of their week organising delivery instead of making commercial decisions.
These patterns suggest a gap in capacity, capability or the way work is managed. Separate them before approaching suppliers. Another pair of hands can clear a production backlog. It will not automatically resolve an unclear proposition or a campaign that reaches the wrong audience.
The expanding range of marketing skills also makes it unrealistic to expect every generalist to be equally confident in analytics, creative production and specialist media. Identify the expertise the business needs, then decide whether to develop it internally or access it externally.
Fix Approval Problems Before Adding More People
If every advert passes through six stakeholders with conflicting opinions, an agency inherits that problem. More production capacity may create a larger queue of unfinished work.
Agree who writes the brief, who checks factual accuracy and who makes the final decision. Feedback should explain whether the work answers the brief, rather than collecting personal preferences from everyone who sees it.
Only 10% of respondents in a 2025 global survey of marketers, agencies and in-house teams said ideas were always assessed against clearly defined criteria. Agree how creative will be evaluated before commissioning more ideas.
When briefing an agency, include the commercial problem, intended audience, available evidence and practical constraints. “Make us more visible” still leaves too much for the delivery team to guess.
Which Work Should Stay In-House?
Keep an accountable internal owner for business priorities, budgets and final approvals. Customer knowledge should also remain accessible inside the organisation, even when an agency helps gather or interpret it.
Consider handing over work that needs specialist judgement, fluctuates heavily in volume or benefits from experience across multiple advertisers. For example, paid search management might require a more experienced approach to account structure and measurement than the current team can provide. Paid social may need closer coordination between media decisions and creative testing.
Imagine an internal team that understands its customers well but cannot produce enough campaign variations for a product launch. A defined creative assignment may solve the immediate problem. If those variations also need new audiences, landing pages and budget decisions, a broader campaign responsibility makes more sense.
The handover should follow the work's dependencies. Splitting every small task between different suppliers can leave the internal team doing more coordination than before. This is one reason to consider an integrated agency when creative and media decisions need to happen together.
When Is It Time to Bring in an Agency Instead of Doing Everything In-House?
Is an Agency Better Value Than Another Hire?
Compare equivalent responsibilities. An agency proposal covering strategy, production and media management cannot be judged fairly against one salary that excludes those additional skills.
For an internal hire, account for recruitment, employer costs, software, training and management time. For an agency, separate fees from media spend, production costs and any third-party charges. Check what happens when the scope changes.
Budget pressure makes this discipline worthwhile. In 2025, 59% of CMOs surveyed lacked sufficient budget to execute their strategy. The respondents predominantly represented large companies, so this is context rather than a budget benchmark for every business.
A permanent hire is sensible when there is enough consistent work for a clear role and the business can develop that person. An agency becomes more attractive when the requirement spans several disciplines or changes substantially through the year. A freelancer may suit a bounded task with a strong internal brief and reviewer.
Start With a Scope You Can Evaluate
Define an initial assignment around a real business need. Set a baseline and agree what improvement should look like. That could be shorter production lead times, stronger creative performance or better qualified enquiries, depending on the work.
The industry's increasing focus on measurable strategic value reinforces the need to assess an agency's contribution beyond output volume. More adverts are only valuable if they solve the problem you hired the agency to address.
Document account ownership, access permissions, reporting responsibilities and the handover process. Agree a review point that allows enough time for the work to have an effect. Where the main gap is knowledge, targeted marketing workshops may be a better first investment than ongoing outsourced management.
How One Day Agency Can Help
Bring One Day the work that is stuck, the results you need and an honest picture of your team's capacity. We can shape a practical scope across creative, media and digital, with clear responsibilities on both sides.
The starting point might be a campaign, a specialist channel or a review of how the current activity fits together. The relationship should give your team clearer decisions and more room to do its own job well.
“Outside support earns its place when it removes a constraint your team cannot reasonably solve alone.” - Ricardo Seixas, CEO, One Day Agency
References
CIM: Top 5 Marketing Challenges for 2025
IPA: The BetterIdeas Project findings, 2025
Gartner: 2025 CMO Spend Survey
IPA: 2025 Annual Review, published May 2026
FAQs
How big should a business be before hiring an agency?
There is no minimum company size. The relevant questions are whether the work needs external expertise and whether the available budget can fund both delivery and meaningful campaign activity.
Can an agency work alongside an existing marketing team?
Yes. Name an internal owner and agree who handles strategy, execution and approvals. Shared access to relevant information prevents duplicated work.
Should we start with a project or a retainer?
Choose a project for a defined outcome and end point. A retainer is more suitable for recurring responsibilities that require ongoing decisions and optimisation.
What should we measure when reviewing an agency?
Use the measures agreed in the brief, alongside delivery quality and collaboration. Distinguish business outcomes from activity totals and allow for the campaign's buying cycle.
