You've already decided you need an agency, if you're still at that stage, start with when to hire a performance marketing agency. Now you have two, three, maybe four proposals on the table, and they all say similar things: "we're results experts," "we work with data," "we have proven case studies." The problem isn't a lack of information, it's that there's no common standard for comparing them. This guide gives you 8 concrete criteria, applicable to any agency, so the comparison stops depending on who has the best pitch.
Why comparing based on "who promises more" is the wrong approach
Every agency defines "results" its own way: one talks about ROAS, another about leads, another about "growth." Without a common baseline, comparing two proposals means comparing different things under the same label. The solution isn't asking each one to speak the same language, it's having your own fixed criteria, set in advance, to evaluate all of them equally.
The 8 criteria
| Criterion | What to look at | How to spot it |
|---|---|---|
| 1 · Real specialization | Whether the focus is measurable acquisition and conversion, or whether attention is split across branding, content, and ad spend | Ask to see the team structure: are there dedicated media buyers, or does the same person do everything? |
| 2 · How they measure success | Whether they report CAC and profitability, or reach and engagement | Ask for a sample report (anonymized) from a current client, see how to read your agency's report |
| 3 · Measurement methodology | Whether they understand why platforms don't match each other and how they resolve it | Ask how they handle attribution when Meta and Google claim the same sale, see attribution in digital advertising |
| 4 · Capacity per account | How many accounts each media buyer manages, and whether there's a monthly client cap | Ask for the number directly, a serious agency knows it off the top of their head |
| 5 · Real scope of service | Whether they only manage ad spend, or also touch landing pages, CRO, or sales follow up | Ask what happens if the problem isn't the campaign but the website or the CRM, see website optimized for conversion and lead follow up |
| 6 · Commercial structure | Minimum contract, payment model (flat fee, % of spend, mixed), and exit terms | Get it in writing before signing, not during the sales meeting |
| 7 · Verifiable track record | Years in business, number of accounts managed, third party reviews, not future promises | Look up the agency on Google Business Profile, LinkedIn, and independent directories |
| 8 · Onboarding process | Whether they audit the account and the business before proposing strategy, or whether the proposal arrived without seeing your data | If they gave you a results number before asking for access to your account, that's a red flag, see the red flags in when to hire an agency |
Comparison matrix (template)
Copy this table and fill it out for each agency you're evaluating, scoring each criterion from 1 to 5:
| Criterion | Agency A | Agency B | Agency C |
|---|---|---|---|
| 1. Real specialization | , | , | , |
| 2. How they measure success | , | , | , |
| 3. Measurement methodology | , | , | , |
| 4. Capacity per account | , | , | , |
| 5. Real scope of service | , | , | , |
| 6. Commercial structure | , | , | , |
| 7. Verifiable track record | , | , | , |
| 8. Onboarding process | , | , | , |
The goal isn't for one agency to score a perfect 5 across all eight criteria, it's to identify where each one falls short, and whether that matters for your specific case. An agency with limited capacity (criterion 4) may make up for it with more focus per account; one without in house CRO (criterion 5) may still be the best fit if you already have that covered internally.
A real example of how this looks applied
To keep the matrix from feeling abstract, here's how KLIV answers some of these criteria, with public, verifiable data:
- Specialization (criterion 1): exclusively focused on Meta Ads, Google Ads, and TikTok Ads, no branding or community management services.
- Capacity per account (criterion 4): capped at 3 new clients per month, to sustain management quality over volume.
- Verifiable track record (criterion 7): 12 years in the market, more than 80 companies managed across 9 countries.
- Commercial structure (criterion 6): minimum 4 month contract, the time an account typically needs to accumulate enough data and optimize.
This doesn't replace filling out your own matrix, it's an example of the kind of concrete answer you should be able to get from any agency you're evaluating, KLIV included.
Common mistakes when comparing
Comparing only price or fee. Without the other 7 criteria, the lowest price can end up being the highest CAC.
Getting swayed by whoever promises the highest number. As covered in when to hire an agency, no one can promise a result without auditing the account first.
Not asking every agency to answer the same criteria. Without a common baseline, it's impossible to compare apples to apples.
Prioritizing the sales pitch over the audit process. The quality of the questions they ask before proposing anything often says more than the proposal itself.
Frequently Asked Questions
What's the most important criterion when comparing agencies?
There isn't just one, it depends on how much of the rest of your operation is already sorted out. For most businesses, real specialization and how success is measured are the ones that most quickly separate a performance agency from a generalist.
Is it a bad sign for an agency to have a limited number of clients per month?
No, it's usually the opposite: it indicates they prioritize management quality per account over taking on as much volume as possible.
Should I choose the cheapest agency?
Price is one criterion among many, not the only one. A cheaper agency that doesn't measure well or spreads its attention across too many accounts can end up costing more in real CAC than one with a higher fee but better execution.
How is this different from knowing when to hire an agency?
They're two different decisions: when to hire helps you decide whether to move from in house management to an agency; this guide helps you compare several proposals once you've already decided to hire one.
Conclusion
Comparing agencies shouldn't depend on who puts together the best presentation, it should depend on concrete answers to the same 8 criteria, applied equally to all of them. An agency that answers with verifiable data, without dodging, is already telling you something important about how it will handle your account.
Want to apply these 8 criteria to your own evaluation? Book a free audit with KLIV, we're happy to answer each one with our real data. Book a call →