How to Choose a Google Ads Agency: What to Check Before You Sign

Choosing a Google Ads agency decides whether your ad budget works toward sales or disappears into campaigns nobody outside the agency understands. The difference between a good partner and a mediocre one rarely shows up in the first sales call. It surfaces two or three months in, when you need to pull data from the account or ask why the campaign isn't growing. Below are concrete criteria you can check before you sign anything.

Who Actually Runs the Campaign — You or the Agency

A Google Ads campaign should run on an ad account registered to your company, with the agency getting manager-level access. On an account the agency owns, your brand is just one of many clients under its client center (MCC). That difference has concrete consequences: if the agency owns the account, ending the relationship means losing campaign history and the conversion data your bidding strategies learned from, and the next agency starts from zero.

Checking this takes five minutes: ask for access to a Google Ads account (ads.google.com) registered to your company email, not the agency's inbox. You need admin access on it, because only admins give and change access levels and can unlink the agency's manager account (Google Ads Help). A refusal, or an explanation that “it's just more convenient this way,” is a warning sign.

What It Costs to Run a Google Ads Campaign — Pricing Models

Google Ads agencies typically charge under one of three models (approximate rates from our experience): a percentage of ad spend (usually 10–20%, dropping as budgets grow), a flat monthly retainer (usually PLN 2,000–5,000, regardless of ad spend), or a hybrid model, meaning a lower base fee plus a bonus tied to a result, such as cost per lead falling below an agreed threshold.

Any of these models can work well. The problem shows up when an agency can't clearly explain what you're paying for, or when a percentage fee grows alongside the budget without any added scope of work. A bigger budget doesn't automatically mean more optimization work.

Does Google Partner Status Actually Mean Anything

A Google Ads certification and Google Partner badge confirm an agency knows the platform's interface and fundamentals. They don't confirm it can run a profitable campaign in your industry. Partner status requires minimum spend across managed accounts, certification for at least half of the account strategists, and an optimization score of at least 70% (Google Ads Help). Optimization score is Google's estimate based on statistics, settings, and recommendations (Google Ads Help), so it doesn't tell you whether a campaign makes money or whether conversion tracking is correct.

Experience in your specific business model tells you more. An agency that has run e-commerce accounts for years will structure a Performance Max campaign differently than one specializing in B2B leads. Ask directly for two or three accounts in your industry, and how budget was split across campaign types there.

How to Verify an Agency's Case Studies and Reviews

The most reliable way to check an agency's reputation is on third-party platforms with reviews verified by paying clients, like Clutch.co, where the agency can't moderate content itself. The average rating matters, and so do the number of reviews and whether they're from the last 12 months or several years old.

• Ask to talk to one current client in a similar industry: an agency with results to show usually says yes
• Check whether a case study shows concrete numbers (cost per conversion, ROAS, number of leads) instead of vague claims about "increased visibility". An example from our work: in the Falcon Car Rental case study, Google Ads ROAS rose from about 4.2× to 8.27× and revenue from the channel grew 74% year over year
• Ask how long that client has worked with the agency: length of the relationship says more than a single good month
• Check the agency's Clutch.co and LinkedIn profile for whether case studies and communication are current

What to Check in a Google Ads Agency Contract

A Google Ads agency contract should clearly state the notice period (in our experience, usually 1–3 months), what scope of work the monthly fee covers, and who owns the creative assets and account access after the relationship ends. A contract with no clear notice period, or one that auto-renews for another year, is worth reading more carefully.

• Notice period — in our experience, usually 1–3 months; a longer one only makes sense in exchange for something, like a lower fee
• Account and data ownership — who keeps admin access after the relationship ends, and whether conversion data gets exported
• Scope of work — whether the fee covers Search only, or also Shopping, Performance Max, Display, and landing page optimization
• Industry exclusivity — some agencies won't work with direct competitors in the same category; ask outright
• KPIs written into the contract — if an agency commits to a specific result, it should be written down with a definition of how and when it's measured

Red Flags That Should Make You Look Elsewhere

The five warning signs below come up most often: from no access to your own Google Ads account, through a guaranteed result (like "we guarantee 5x ROAS") promised before the agency knows your industry and account history, to reporting with no link to sales. If you already work with an agency, also go through the signs that your agency is burning through your budget.

Questions Worth Asking on the First Call

The seven questions below let you tell, in a 30-minute call, whether an agency understands your business model or is selling the same package regardless of client industry.

• Which Google Ads account will the campaign run on, and who has access to it after the relationship ends?
• What does the fee structure look like, and what's included: optimization, reporting, consultations?
• How many accounts in my industry or a similar business model do you currently run?
• How do you track conversions: server-side, or just the standard Google Ads tag?
• How often, and in what format, will I get a results report?
• What's the contract's notice period, and what happens to the account after it ends?
• Can you show a sample monthly report from another account, with client data blurred out?

Before signing a contract for Google Ads management, go through this list point by point. A good agency will answer every one of these questions without hesitation, because that's how it already works day to day. The answer about conversion tracking is easier to judge once you know the state of your own setup: check it with our GA4 audit. At Zest, we always run campaigns on the client's own account, with server-side conversion tracking and reports that show sales alongside clicks. If you're weighing a change of agency, let's talk about your account: as a digital marketing agency we start every conversation with a free review of your current campaign.

See also: the ranking of Google Ads agencies in Poland and how much to spend on Google Ads and Meta Ads in 2026.

FAQ