How to choose a marketing agency

Choosing a marketing agency is harder than choosing most suppliers, because you usually can’t judge the work until months after you’ve paid for it. The pitch is polished, the case studies are real but selective, and the person presenting is often not the person who will run your account.

If you haven’t yet decided whether an agency is the right kind of help, start with agency, freelancer, consultant or in-house hire. This guide assumes you have.

Start with the outcome, not the service

Agencies sell services: SEO, paid search, paid social, content, brand. Businesses need outcomes: more qualified enquiries, a lower cost per sale, a brand that doesn’t look like a competitor’s.

If you brief on the service, you’ll get what you asked for whether or not it was the right thing. If you brief on the outcome, a good agency will tell you when the service you had in mind is the wrong route.

Before you talk to anyone, write down:

• What has to be true in twelve months for this to have been worth it
• What you spend now, and what a new customer is worth to you
• What you’ve already tried, and what happened
• Who will work with the agency internally, and how much of their time you can commit

The last point matters more than it sounds. Many engagements stall on the client side — approvals, access, copy sign-off, someone to answer questions about the product. How to write a marketing brief turns these notes into something agencies can quote against.

Specialist or full service

A specialist does one thing to a higher standard. A full-service agency covers more ground and gives you one relationship to manage.

The honest trade-off is depth against coordination. Specialists usually beat a generalist in their own discipline, but someone has to keep them pulling in the same direction. If nobody in your business has the time to do that, one agency is often the better answer even if each discipline is a little weaker.

Be wary of a small agency that claims real depth in everything. Being good at search and paid media is common. Being good at search, paid media, brand, design, video, PR and email at once is not.

Find out who actually does the work

This is the most useful question in the process, and the one most often skipped.

Ask directly:

• Who will run this account day to day, and can I meet them?
• How many other accounts do they look after?
• What is done in house, and what is subcontracted?
• Who writes the copy and who builds the pages?
• What happens when that person leaves?

Senior people often win the work and more junior people deliver it. That’s not automatically a problem, as long as you know, the price reflects it, and there is real senior oversight rather than a name on an organisation chart.

Keep ownership of everything

Your business should own its accounts and data, with the agency given access rather than possession. This is dull right up until a relationship ends badly.

Invite the agency to your accounts through each platform’s user or partner access. Never hand over your passwords, and be sceptical of anyone who asks for them. A professional agency will expect this and already have a process for it.

If an agency wants to run your advertising through its own ad account, understand what you’re giving up: when you leave, the campaign history stays with them.

Agree how success will be measured

Agree the measure before the work starts, in writing, along with who reports it and how often.

Good reporting ties back to the business — enquiries, qualified leads, cost per customer, revenue. Weaker reporting leans on impressions, reach, followers and rankings: real numbers that can all rise while sales stay flat. What to measure in your marketing covers which numbers to ask for.

Agree two things up front:

1. The baseline. What the numbers are today, taken from your own analytics and sales records, before anyone changes anything.
2. The timescale. Paid advertising gives useful data within weeks. SEO and content usually take months. Judge each on the right clock or you’ll cancel good work at the wrong moment.

Contracts and notice

Read the minimum term and the notice period. Twelve-month terms with three months’ notice aren’t unusual, and can be reasonable for slow-burn work such as SEO, but choose them knowingly.

Check specifically:

• The minimum term and notice period
• Whether fees rise, and when
• What happens to work in progress if you leave
• Who owns the creative, copy and code when the contract ends
• Whether ad spend is billed through the agency or paid by you directly to the platform

That last point deserves care. If your media budget flows through the agency, you’re extending them credit and losing a clear view of what reached the platform.

Red flags

• Guaranteed rankings or results. Nobody controls Google’s results. Google’s own advice on hiring an SEO says no one can guarantee a #1 ranking (opens in a new tab).
• Pressure to sign this week. Expiring discounts are a sales tactic, not a commercial reality.
• Vague deliverables. “Ongoing optimisation” isn’t scope. Ask what you get each month, in units.
• No questions about your business. An agency that pitches before it understands your margins is selling a template.
• Case studies with no numbers, or numbers with no starting point — which amounts to the same thing.
• Offers to write or buy reviews for you. Fake reviews are unlawful in several markets, including the UK since 6 April 2025 (opens in a new tab) and the US under an FTC rule in force since 21 October 2024 (opens in a new tab).

Advertising rules in your market

Marketing is regulated everywhere askBizly’s readers are based, and responsibility sits with you as the advertiser, not only with the agency that made the ad. Ask any agency how they keep your advertising within the rules. If they’ve never thought about it, price that risk in.

This is orientation, not legal advice. Sector rules — financial services, health, alcohol, gambling — add further requirements in every market.

Compare your shortlist like for like

Narrow it to two or three agencies, then send every one the same brief, with the same budget and the same measure of success. If each is quoting against a slightly different understanding, the proposals can’t be compared, and the cheapest will simply be the one that scoped least.

When the proposals arrive, check each one before you sign, and use what agencies charge to sense-check the fees.