Short answer
When choosing a performance marketing agency, look at how it sets up measurement, whether it judges success by platform reports or by profit, whose name the ad accounts are in and whether its fee is shown separately from the media budget. Creative testing, cross-channel budget logic and sector experience also matter. Avoid agencies that guarantee results.
9 min read
What does a performance marketing agency do?
A performance marketing agency is a team that plans the advertising budget around measurable outcomes such as sales, qualified leads or appointments, runs campaigns on channels such as Google, Meta, LinkedIn and TikTok, and reallocates the budget according to the results achieved. The job is not just about setting up campaigns. Measurement, landing pages, creative production and reporting are part of it too; knowing this from the outset helps you read proposals correctly.
This article is a checklist designed to help you compare proposals from different agencies against the same criteria. If you are curious about how we work, see our performance marketing service page. Here we look at things from the side of the business making the choice, not the agency.
What criteria should you use to choose a performance marketing agency?
How does it set up measurement?
Every decision in performance marketing rests on measurement. Ask the agency whether it audits your existing GA4, Google Tag Manager and ad platform conversion setup when it starts. Installing Meta Pixel together with the Conversions API, consent-compliant measurement and, where possible, sending sales or CRM data back to the platforms are signs of a measurement plan that is taken seriously. An agency that leaves measurement for later will manage your budget on the wrong signal.
Does it measure success by profit or by platform figures?
Every ad platform counts its own contribution by its own rules. An agency that adds up platform reports can report more conversions than the sales that actually happened. A good agency compares platform data with analytics and sales data, and alongside ROAS it includes profit indicators that account for product cost and returns. Also check whether it reports sales from brand searches separately from new customer acquisition.
Does it have a creative testing process?
As targeting options become automated, what finds the right person is increasingly the creative itself. Ask the agency who produces the creatives, what hypothesis each test is built on and how winners and losers are recorded. "We prepare a few visuals every month" is a production schedule, not a testing process.
Whose name are the ad accounts opened in?
Ad accounts, analytics properties, the Tag Manager container and the product catalogue should be opened in the business's name, with the agency accessing them as an authorised user. That way, if you part ways, the account history, audience lists and conversion data stay with you. Ask for this to be stated clearly in the contract.
Is the fee model transparent?
The agency fee and the media budget paid to the platforms should be shown separately. In the most transparent setup, platform invoices are issued directly to the business and the agency invoices only its service fee. Remember that under a fee model tied to budget, the agency's income grows as spend grows; make sure decisions to increase the budget are based on profit data. For more on the models, see our article on digital marketing agency fees.
How does it allocate budget across channels?
Search ads capture existing demand, while social and video ads create demand among people who have not started searching yet. Find out what role the agency gives each channel, whether it allocates budget by average results or by the additional results that extra spend brings, and whether it sets aside a separate share for new experiments. An agency that specialises in a single channel and leaves the others in the background may pile your budget into that channel too.
Does it know your sector and sales model?
In areas such as e-commerce, corporate sales, healthcare and real estate, the buying cycle, advertising policies and measurement needs differ greatly. A team that has worked with a similar sales model asks the right questions sooner. Even so, judge sector experience not by a list of client logos but by how concretely the agency can explain its approach in that sector.
Who will work on your account?
The senior people you meet during the sales process may not be the team that manages the account day to day. Find out at the start who will work on the account, whether strategy and execution sit in the same team and what the meeting schedule will be.
Do the reports help you make decisions?
A good report contains not only last period's figures but also the decisions that follow from them: which campaign will be scaled, which will be paused, which test will start. Ask the agency for a sample report. Check whether each metric's definition is written down, which source the data comes from and whether there is a plain summary for management. A live reporting dashboard lets you see where things stand without waiting for the end of the period.
Can it work on your site and your offer?
Ads bring the click, but the sale happens on the site. Ask whether the agency has recommendations on landing pages, forms and checkout flow, and whether it can test those changes if needed. A team that looks for problems only in the ad account will suggest sending more budget to a site with a low conversion rate.
What questions should you ask at proposal stage?
Ask the shortlisted agencies the following questions and request written answers. How concrete the answers are shows the agency's way of working better than the pitch does.
- How will you audit our measurement setup at the start, and which conversions will you define as primary goals?
- Which indicator will you use to measure success, and how does it connect to our profitability?
- Will you be able to send our sales or CRM data back to the ad platforms?
- Who will produce the creatives, and how will you plan and record tests?
- What logic will you use to allocate budget across channels, and when will you rebalance it?
- Whose name will the ad, analytics and catalogue accounts be opened in?
- How will the agency fee and media budget be separated on invoices, and could extra items appear later?
- Which raw data will we have access to in reports?
- When the contract ends, how will accounts, audiences and creative files be handed over?
Which situations are red flags?
- Promised results: A promise of specific sales, costs or returns. Because price, competition, stock and your site's performance also shape the outcome, no agency can control this.
- Opening accounts in the agency's name: If ad or analytics accounts belong to the agency, you lose your account history and data when you part ways.
- Hidden fees: Set-up, tool licence, reporting or creative fees that surface later.
- Unitemised invoicing: Platform spend invoiced through the agency without a line-by-line breakdown.
- Click and impression reports only: Reports that are not tied to business outcomes and give no access to raw data.
- Hard-to-exit contracts: Arrangements with no initial period or reasonable termination terms.
Is an in-person meeting necessary when choosing an agency in Istanbul?
Performance marketing can be run remotely; accounts, reports and meetings are managed online. Even so, a face-to-face workshop, especially at the start, speeds up understanding of the business model, margins and sales process. If you work with an agency in Istanbul, holding the first discovery meeting and period reviews in person makes it easier to bring your sales and operations teams into the process.
Proximity alone should not be the reason for your choice. Having the agency's office in your city does not replace the criteria above. What really matters is a regular, predictable rhythm of communication and being able to sit at the same table as the team when needed. If you are expanding into international markets, also ask about the agency's experience of running campaigns in different languages and markets.
How do you finalise the choice?
Ask the shortlisted agencies to look at your ad accounts with read-only access and carry out a short preliminary review. Whether the findings are based on your data and which priorities they set shows how the agency thinks. Then starting with a time-limited initial period, with written goals and a written measurement method, reduces the risk for both you and the agency.
Once measurement is set up correctly, the most discussed topic is return on ad spend; we cover the profit side of this in our article on ROI-focused performance marketing. For our approach to search and shopping campaigns, see our Google platform page, and for a review tailored to your business, get in touch via our contact page.
Frequently asked
- What is the difference between a performance marketing agency and performance marketing consultancy?
- An agency sets up campaigns, manages them day to day and takes on creative and reporting. Consultancy defines the strategy, measurement plan and budget decisions and leaves execution to the business's own team. Consultancy usually suits firms with their own ad team, while the agency model suits those without one. The models can also be combined.
- Is a performance marketing company the same as a digital marketing agency?
- Not always. A digital marketing agency may offer a broad range of services such as social media, content and SEO. A performance marketing company focuses on managing paid channels, measurement and budget decisions according to measurable business outcomes. You can tell which model an agency works in by looking at what it measures success by.
- When should results be reviewed after starting with an agency?
- The first period is spent fixing measurement and letting platform algorithms learn; changing campaigns frequently during this time disrupts learning. Meaningful data appears sooner in search ads and later in demand-generating channels. Setting the review schedule in writing at the start and comparing each period with the same indicators is the soundest approach.
- Does it make sense to work with an agency on a small budget?
- With a small budget, it is better to reduce the number of channels and focus on campaigns that capture existing demand. Where the agency fee stays very high relative to the media budget, consultancy or a set-up focused project may be more efficient. Platforms change their minimum budget conditions from time to time; check current conditions in the ad dashboard.