How to Find the Best Google Ads Agency for E-Commerce
Searching for the right Google Ads agency feels like searching for a good mechanic: from the outside they all look the same, and only when it's too late do you find out whether you ended up with the right one. We show you concrete criteria, critical questions and red flags that separate a good agency from a mediocre one.
Searching for the right Google Ads agency for your online shop feels like searching for a good mechanic: from the outside they all look the same, and only when it's too late do you find out whether you ended up with the right one. The problem is that a wrong choice doesn't just cost you monthly agency fees — it also costs you burned ad budget and lost revenue.
In this guide, you'll learn which concrete criteria actually separate a good agency from a mediocre one, which questions you should ask in the first conversation, and which warning signs you must not ignore.
Why the Best Google Ads Agency Isn't the Biggest One
A common misconception: the bigger the agency, the better the results. In practice, the opposite is often true. Large agencies have complex internal structures in which the senior who impressed you in the sales pitch never touches your account again after the contract is signed. The actual work is done by a junior account manager who handles twenty other accounts in parallel and has maybe two to three hours per week for each of them.
Two to three hours per week is enough to generate reports and make a few superficial optimisations. It's not enough to truly get inside your shopping feeds, analyse your competition, test new campaign strategies or solve complex problems in your conversion tracking.
The best Google Ads agency for your e-commerce shop isn't automatically the one with the most prominent clients or the most awards. It's the one where genuinely experienced specialists actually have enough time for your account.
The Most Important Selection Criteria in Detail
Specialisation in E-Commerce
Google Ads for service providers, B2B or lead generation works fundamentally differently than Google Ads for e-commerce. An e-commerce agency needs a deep understanding of how Google Shopping and Performance Max work, what an optimised product feed looks like, how to handle different margins per product, how seasonal fluctuations are modelled, and how Merchant Center, Analytics 4 and your shop system interact.
In every first conversation, ask for concrete e-commerce references, for industries the agency has experience in, and for concrete numbers: what ROAS development have they achieved for comparable shops? With what setup? How long did it take? A serious agency can answer these questions concretely — anonymised if necessary.
Access to the Senior Expert Running the Show
The most critical question in the first conversation: who will actually work on my account, and how much time will that person invest? Don't settle for vague answers. A reputable agency can tell you by name who your point of contact is, what qualifications that person has, and how many accounts they manage in parallel.
We deliberately run our agency as a two-person team, because we want to make sure every client works directly with decision-makers who also sit at the account operationally. That's not a business model for a hundred clients — it's a deliberately limited approach. Not every agency has to be set up this way, but regardless of agency size, you should understand who is really working on your account.
Transparency in Reporting and Account Access
Your Google Ads account belongs to you. A good agency insists that the account runs in your name and that you have full admin access at all times. Any agency that denies you this access, or only shows you reports instead of raw data, is either trying to lock you in or hiding something.
Proper reporting doesn't just show you pretty graphs with rising curves — it shows you concretely what was done in the past month, which hypotheses were tested, which worked and which didn't. Reports without commentary on the work are pointless, because you can't judge whether improvements are coincidence or the result of real work.
Clean Handling of Conversion Tracking
Nine out of ten Google Ads accounts we see from prospects have problems in their conversion tracking. Duplicate counting, missing transactions, wrong values, returns that aren't passed back. The result is that campaigns are optimised on false signals, which renders even the best strategy absurd.
Ask the agency explicitly about its approach to the tracking setup. Do they use enhanced conversions, server-side tracking or similar techniques? How do they handle cookie consent? How are returns and cancellations accounted for? An agency that can't give you clear answers here will steer your campaigns based on flawed data.
Clear Statements About Expectations and Reality
Reputable e-commerce marketing agencies don't promise specific ROAS figures in the first conversation. Anyone who guarantees you a ROAS of 8 or 10 in a sales pitch — without knowing your account, your products, your margins or your market — is either making empty promises or planning to manufacture those numbers through creative metric definitions.
An honest agency tells you: we don't know what's possible before we look deeper into your account and your market. We can give you a realistic range after an analysis, and we'll also tell you if we think your shop has structural problems that even the best campaign can't compensate for.
Which Questions to Ask in the First Conversation
Prepare for every first conversation with concrete questions. The answers are more revealing than any website or pitch deck.
Ask how many e-commerce clients the agency currently manages. Not has had — actively manages. Ask about the average length of client relationships. If the agency keeps many clients for only six to twelve months, that tells you something.
Ask for a concrete client example where something went wrong, and what the agency learned from it. An agency that claims to never make mistakes is either lying or doesn't reflect on its work. The best agencies are transparent in assessing their own work.
Ask about the contract term. If the agency demands a commitment longer than three months, ask why. Good work doesn't need legal client retention. Ask what an offboarding would look like if you ever wanted to part ways.
Red Flags That Should Make You Walk Away Immediately
There are certain signals that should always lead you to rule out an agency, no matter how good the rest of the offer looks.
If an agency insists on controlling access to your account without you having equal access, that's a clear no. If it makes concrete performance guarantees in the very first conversation, without having seen your account, that's a warning sign. If the contract term is longer than six months with no option to cancel, you should at the very least renegotiate.
If the agency isn't willing to tell you exactly who works on your account and how many hours per month are invested, that's a problem. If it can't have an honest discussion about risks and realistic expectations, and instead just strings together sales arguments, you should keep looking.
Conclusion: What Really Makes the Best Agency
The best Google Ads agency for your online shop isn't the one with the most awards or the biggest names. It's the one where genuinely experienced specialists have time for your account, that works transparently, that doesn't tie you down with long contracts, and that communicates honestly — even when the truth is uncomfortable.
Take your time with the selection. A quick contract with the wrong agency will end up costing you far more than two extra weeks of research and conversations.