The question is harder than it looks
"Best performance marketing agency" returns 60 results that all use the same four stock photos and promise the same four KPIs. Here is how to actually pick one.
The seven questions
1. Who is on the account? Ask for names and titles. If the partner is on the pitch and a senior-manager-plus-pod runs the day-to-day, that is the model that works. If a junior is the primary point of contact within 90 days, that is the model that loses.
2. How do you measure incrementality? A performance agency that cannot explain geo-split holdouts, conversion lift, and MMM is not a performance agency. They are a media-buying desk.
3. How many creative variants do you ship per week? Under 20, they are outsourcing. Over 50, they are diluting. The sweet spot is 30–50 per week per client with a documented hypothesis per variant.
4. What is your take on attribution? Every honest answer starts with "attribution is broken, and here is how we work around it." Any answer that starts with "our proprietary attribution model" is a red flag.
5. Will a chunk of your fee be at risk against a KPI? If yes, they believe in the work. If no, they do not.
6. When will you tell us to stop spending? A partner that has never told a client to cut budget is not a partner.
7. Can we talk to a current client — in the category we are in — with no one from your team on the call? This is the most important question. Most agencies will not allow it. The ones who will are the ones to hire.
What doesn't matter
- Award case count.
- A shiny "proprietary technology platform" (it is a spreadsheet).
- How fast they can start (urgency is a red flag).
- Flat fee, retainer, or performance pricing (structure is not the agency).
The honest version
A real performance marketing agency is 60% measurement rigor, 30% creative production, 10% media execution. Most agencies flip it: 60% execution, 30% creative outsourcing, 10% measurement. The first version wins. The second version drifts until a new CMO fires them.