Marketing retainer vs in-house hire: the honest maths for a mid-market business

This piece is for the managing director or finance director sitting in front of a spreadsheet, deciding whether to hire a marketing manager at £55k or take on a partner at £8k a month. We have sat across that table dozens of times. Here is what we say.

The fork in the road

The conversation almost always starts the same way. The business has grown — perhaps £4m to £12m over four years. Marketing has been done by the MD's spare time, a niece who is good at Canva, or a string of three different agencies that did not really land. Someone on the board has said "we need a proper head of marketing", and a job spec has been written.

Then the maths happens. £55k base, plus on-costs, plus tools, plus the recruiter's fee. Suddenly you are at £75k all-in, before that person has done anything.

So you ask: should we just use an agency? And the agency quotes you, say, £8k a month — £96k a year — and you think, well, that is more than the hire.

The number is real, but the comparison is wrong, because you are comparing one job to a different job.

The real cost of an in-house hire

The all-in cost of a £55k marketing manager in the UK in 2026 is, by our calculation, around £85k a year. Here is what gets missed:

• Employer NI, pension and apprenticeship levy: roughly +18% on base
• Recruitment fee: typically 20–25% of base, one-off
• Software stack: HubSpot or similar (£8k–£20k a year), Adobe / design tools, analytics (£2k–£8k), a CMS
• Outsourced execution they will still need: paid media management, SEO, technical web work, video, brand. Whatever you hired this person to do, they cannot do all of it. They will sub-contract some of it. You will pay for it. It is the same arithmetic whether the role is broad marketing or a single hire to manage the website — one person rarely spans every job the title implies.
• Onboarding cost: three to six months before they are operating at capacity. Real, but rarely booked.
• Holiday, sickness, parental leave: factored at around 8% of working capacity over the year.

Add it up properly and you are at £90k to £120k of effective annual cost for the first year. The next year, if they stay, drops to about £85k to £95k. The average tenure of a B2B marketing manager in a mid-market business is, in our experience, between eighteen months and three years.

The honest comparison is not £55k vs £96k. It is £100k of in-house cost for one generalist, vs the same money for a team of senior specialists with the bench depth to absorb a holiday or a maternity leave.

What a retainer actually buys you

At a Nine Stones retainer of, say, £8k a month, what you are paying for is:

1. Senior strategy. One partner sitting on your monthly call, in your annual plan, in your board update. Twenty-plus years of experience, not the four years your hire will have.
2. A team of specialists. Paid media, SEO, CRM, analytics, design, content — pulled in as the work demands, not loaded into one job description.
3. The tooling already paid for. Analytics suites, SEO platforms, paid media management tools, design software. Included in the retainer.
4. Continuity. No notice periods, no sickness gaps, no recruiter fee if it does not work out. A retainer can be ended with thirty days.
5. Bench depth. When you need a one-off — a rebrand, a video, a deep SEO project — it comes from the same team, on the same plan.

What you are not paying for: a face at your desk five days a week.

When an in-house hire is the right answer

We are honest with people about this. There are three cases where the hire is genuinely the better call.

• You have so much marketing happening internally that the orchestration is itself the job. If you are running events, a content team, multiple campaigns and a CRM you sit on every day, you need someone in the building.
• You are in a regulated industry where the work cannot be sent to a third party. Defence, certain parts of financial services, anywhere with security clearance gating the work.
• You have one specific senior person you want to hire. This happens. If you know the person, hire the person.

In all three cases, we have helped clients write the job spec, sit in on interviews, and then partnered with the resulting hire on a smaller scope. There is no rule that says it has to be one or the other.

When a retainer is the right answer

The retainer is the better answer for most mid-market businesses, most of the time. Specifically:

• You are between £2m and £30m of turnover, and marketing is not, today, anyone's full job
• You sell B2B or to a considered consumer audience — not virality, not lifestyle
• You have a sales team, a product team, or a customer team that needs better marketing support, but not a marketing department
• You want senior thinking without the cost or risk of a senior hire

This is what we are built for. It is not the only thing in the market, but it is the thing we do.

The hybrid that usually wins

The pattern we see work best, over multiple years, is this:

• An in-house marketing coordinator or operations role — £30k–£45k, runs the CRM, owns the diary, owns the brand assets, owns the website day-to-day
• A retainer partner — strategy, senior practitioners, specialist execution, monthly cadence

Together, the cost is similar to two in-house hires. The capability is materially greater than either side alone. Most of our long-standing clients run this way.

If you are at the fork in the road and you would like a second opinion on the maths, write to us — or run our six-question fit check first. We will tell you honestly what we would do — including when the answer is "hire, don't retain".