How to Write a Great Agency Brief (With Template)

A great agency brief is the single most effective thing you can do to improve the quality of proposals you receive, reduce wasted back-and-forth, and set your agency relationship up for success. Yet most briefs are either too vague to be actionable or so long they don't get read properly.

This guide explains what belongs in a strong brief, what to leave out, and includes a template you can adapt immediately.

Why the Brief Matters More Than You Think

When you send a brief to multiple agencies, you're asking each of them to invest time in understanding your business, diagnosing a problem, and proposing a solution — all before you've spent a penny with them. A clear brief signals that you're a serious client who knows what you want. A vague brief signals the opposite, and the best agencies — the ones with full pipelines — will deprioritise it accordingly.

More practically: the quality of what you put in determines the quality of what you get back. Agencies can only recommend the right channels, budgets, and approaches if they understand your business well enough to make those calls. A thorough brief gets you genuinely tailored proposals rather than recycled decks.

What to Include in Your Agency Brief

1. Company and Product Overview

Start with the basics — but make them relevant, not generic. Don't just paste in your About Us page. Instead, cover:

• What you sell, and who buys it
• Your price point and how it compares to competitors
• Your key differentiators — what actually makes you different in the market
• Your current revenue scale and growth stage (startup, scaling, established)

2. The Problem You're Trying to Solve

This is the most important section. Be honest and specific. Examples of strong problem statements:

• "We're spending £15,000/month on Google Ads but our cost per acquisition has increased 40% over the last 6 months and we don't know why."
• "We're launching into the UK market and need to build brand awareness among 25–40-year-old homeowners in major cities."
• "Our Facebook campaigns worked well until iOS 14, and we've never fully recovered. We need a new approach to prospecting."

The more concrete you are here, the more useful the proposals you receive will be.

3. Goals and Success Metrics

What does success look like — and how will you measure it? Be specific:

• Good: "Achieve a blended ROAS of 4x within 6 months."
• Better: "Acquire 500 new customers per month at a maximum CAC of £35, while maintaining a minimum ROAS of 3.5x on paid social."
• Avoid: "Increase sales and brand awareness."

If you're unsure what targets are realistic, say so — a good agency will help you set them, but you should at least articulate the business outcome you're working toward.

4. Target Audience

Describe your ideal customer in terms that go beyond demographics. Include:

• Demographics: age, location, income, job title (where relevant)
• Psychographics: values, interests, pain points, motivations
• Buying behaviour: how they discover products like yours, how long the sales cycle is, what objections they have
• Existing customer data: if you have first-party data (email lists, CRM data, purchase history), mention it

5. Budget

This is where many briefs fall down. Advertisers are often reluctant to share their budget, worried it will be "spent to the limit." But agencies can't give you a meaningful proposal without knowing your budget. If you're considering multiple scenarios (e.g., £5K/month vs £10K/month), say so — many agencies will propose options.

Be clear whether the budget covers just agency fees, just media spend, or both. These are very different numbers.

6. Channels (or Your Openness to Recommendations)

Tell agencies which channels you're currently using, which you've tried and stopped (and why), and whether you're open to their recommendations. For example:

• "We're currently running Google Ads and want to expand into paid social."
• "We've tried Facebook Ads before without success — we'd like to understand if our approach was wrong or if it's just not the right channel for us."
• "We're open to any channel recommendations as long as they can be tracked to revenue."

7. Timeline

When do you need to be live? Are there key dates — a product launch, a sale period, an event — that are non-negotiable? Agencies need this context to assess whether they can onboard you in time and to structure a realistic ramp-up plan.

8. What You Already Have

List your existing assets and infrastructure:

• Website and landing pages (and whether they're CRO-optimised)
• Creative assets (photography, video, brand guidelines)
• Analytics and tracking setup (GA4, pixel, conversion tracking)
• CRM or email platform
• Existing ad accounts (and whether you'll provide access or start fresh)

9. Who You're Talking To

Let agencies know how many you're briefing and roughly where you are in the process. Are you in early exploration or close to a decision? Are you comparing 2 agencies or 10? This context helps agencies calibrate the depth of their response.

Brief Template

Here's a condensed template you can copy and adapt:

• Company overview: [Who you are, what you sell, your market position]
• The problem: [What's not working, or what you're trying to achieve]
• Goals and KPIs: [Specific, measurable targets]
• Target audience: [Demographics, psychographics, buying behaviour]
• Budget: [Monthly media spend + agency fees, or total budget]
• Channels: [Current channels, past experience, openness to recommendations]
• Timeline: [When you need to be live, key dates]
• Existing assets: [Website, creative, tracking, ad accounts]
• Process: [How many agencies you're briefing, when you'll decide]

Common Brief Mistakes

• Being vague about budget — "We have budget available" wastes everyone's time. Give a range.
• Hiding problems — If your previous agency underperformed, say so. A good new agency will want to understand why.
• Over-specifying the solution — Brief the problem, not the solution. Let agencies bring their expertise to channel and format decisions.
• Making it too long — A strong brief is 1–2 pages. If it's longer, edit ruthlessly. Agencies don't read 20-page documents at RFP stage.

Ready to Send Your Brief?

Once your brief is ready, use Pick an Agency's matching tool to find agencies that are genuinely suited to your goals, budget, and channels. You can also browse the full directory to build your own shortlist before reaching out.