The short answer.
Ask every agency the same 20 questions, in writing if you can, and judge the answers on evidence: dated results with a named source, a method they can explain, the people who will do the work, measures tied to your enquiries and revenue, and a contract you can leave. Walk away from any agency that guarantees rankings, claims to be number one, or won’t let you own your own accounts.
We are an agency, so read this with that in mind. We have written it the way we would want to be judged, including where our own evidence is thinner than we would like. A weak answer in any one of the five groups below can cost you a year.
- 01 · EVIDENCECan they prove it?
- 02 · METHODCan they explain it?
- 03 · PEOPLEWho will do it?
- 04 · MEASUREMENTHow will you know it worked?
- 05 · CONTRACTCan you leave cleanly?
Four questions in each group, 20 in all. Each group has its own table below, and all 20 are in the scorecard in chapter 10.
Start with Google’s own advice.
Google publishes a short page for anyone thinking of hiring help with search, called “Do you need an SEO?”, on Google Search Central. It is the most useful free starting point, and most buyers never read it. It suggests asking for examples of previous work, whether the agency follows Google Search Essentials, what results they expect and in what timeframe, how they measure success, what experience they have in your industry and your country, how long they have been in business, and how you will communicate.
The same page is blunt about the warning signs. It says no one can guarantee a first-place ranking on Google, and that if an agency promises one you should find someone else. It warns against firms that email you out of the blue, firms that are secretive or won’t explain what they intend to do, and anyone who claims a “special relationship” with Google or a “priority submit”. It also suggests asking past clients whether the service was useful, and giving a new agency only read access to Search Console at first.
What changes for AI search
Many agencies now sell “GEO” or “AEO” work aimed at AI answers. Google’s own page on AI features says there are no additional requirements to appear in AI Overviews or AI Mode, “nor other special optimizations necessary”, and that existing SEO fundamentals continue to be worthwhile. That doesn’t make AI search work pointless: other engines behave differently, and being named in an answer depends on what is written about you across the web. But it does mean an agency should be able to tell you plainly what it does beyond good SEO, and why. Our explainer on AEO, GEO and SEO sets out where the lines sit.
Evidence: can they prove it?
Every agency has a results page. The question is whether you can check any of it. Ask these four first; the answers decide whether the rest is worth asking.
| Question | A good answer sounds like | A bad answer sounds like |
|---|---|---|
| 1. Can you show me a result for a business like ours, with the tool, the dates and what was counted? | “Here is the report, the two date ranges and the exact metric. The screenshot is on the case study, and here is one that went less well.” | “We grew a SaaS client’s traffic by 300%.” No tool, no dates, no client you can check. |
| 2. Can we speak to one or two clients, past or current? | They offer names, let you ask your own questions, and point to dated reviews on platforms they don’t control. | “All our clients are confidential.” The only praise is on their own website, undated. |
| 3. Which of your numbers are tool readings, and which did the client report? | They separate the two without being asked: an analytics report is one thing, a client’s review quote is another. | They blur them, or don’t understand why it matters. |
| 4. Tell us about an engagement that didn’t work. What did you change? | A specific story, told without blaming the client, ending in something they now do differently. | “That hasn’t happened to us.” |
Question 3 matters more than it looks. A number from an analytics report and a number a client wrote in a review are both useful, but they are different kinds of evidence. Here is how we label our own. One of our clients wrote, in a Clutch verified review published on 3 July 2024, that Prolinkage’s efforts increased website traffic by 120% and achieved top rankings for business keywords. That is the client’s own report, not a tool reading, and we say so wherever we use it. The same review scored us 5.0 overall. A tool reading looks different, as the next chapter shows.
How to check a case study.
A case study number means nothing until you know three things. Ask them of every figure an agency shows you, including ours. If the agency can’t answer all three in a sentence each, treat the number as marketing.
- 01 · SOURCEWhich tool, and which report?
- 02 · DATESWhich dates, compared with which?
- 03 · COUNTWhat exactly was counted?
The same three questions work for traffic, rankings, enquiries and AI visibility claims.
A worked example, using our own number
Our headline result for FullTilt Team Development reads: GA4 organic-search key events rose from 13 to 234 (+1,700%) over 1 May-28 Nov 2024 compared with 2 Oct 2023-30 Apr 2024. Here is that number put through the three questions.
| Question | Answer | What to look for |
|---|---|---|
| Which tool and report? | Google Analytics 4, the client’s own property. User acquisition report, first-user primary channel group, Organic Search row, key events column. | A named tool and report you could open yourself, not “our internal data”. |
| Which dates vs which? | 1 May–28 November 2024, compared with 2 October 2023–30 April 2024. Both windows are 212 days long. | Two stated windows of equal length. A single “up 1,700%” with no dates can be any period the agency liked. |
| What was counted? | Key events: actions the site owner marked as important in GA4, from visitors who first arrived through organic search. | Key events are recorded actions. They are not unique leads, sales or revenue, and a good agency says so. |
Notice what the answer does not claim. It doesn’t say “leads”, because a key event is not a lead. It doesn’t say “revenue”, because GA4 didn’t measure revenue here. And the screenshot of the report, with both date ranges visible, sits on the case study so you can check it. When an agency shows you a number, ask for the equivalent screenshot. If they hesitate, you have your answer.
Method: what will they actually do?
A good method can be explained in plain words and changes depending on what the agency finds on your site. A bad one is a package that was decided before anyone looked.
| Question | A good answer sounds like | A bad answer sounds like |
|---|---|---|
| 5. What will you do in the first 90 days, in order, and why that order? | They start by checking what exists, such as tracking, technical health and content against demand, then name the first pieces of work and what each should change. | A fixed package of articles and links a month, the same for every client, decided before they have looked at your site. |
| 6. How does your work fit Google’s Search Essentials? | They know the document, can name the spam policies that matter for your site, and explain how they stay inside them. | “Google doesn’t need to know what we do,” or a blank look. |
| 7. What do you do differently for AI search, and how do you test it? | They say plainly that the foundations are the same as SEO, then describe the specific extra work and a repeatable, dated test across named AI engines. | A “proprietary AI ranking formula”, or a promise to “get you into ChatGPT”. |
| 8. Will you explain every change to our site before you make it? | Yes, with a written change log, an approval step for anything visible, and a way to undo it. | “Leave it with us. You’ll see the results.” |
What an honest AI search test looks like
Question 7 is where the newest claims live, so ask to see a test. Here is one of ours. On 6 November 2026 we asked ChatGPT, Perplexity and Google’s AI Overview which agencies a US B2B company should hire to improve its visibility in AI search. ChatGPT named 8 agencies. Perplexity named 10, drawn from 10 sources, and warned that many such lists are written by agencies themselves. Google’s AI Overview named 6. Only one agency appeared in all three answers, and we did not appear in any of them.
When we asked ChatGPT about us by name, it called us “worth shortlisting”, but it quoted an outdated figure from our own case study and mixed up our founding year. That is what a real test looks like: a stated question, named engines, a date, and results that don’t always flatter the agency. It also shows why a claim like “we appear in ChatGPT” needs the question, the date and a screenshot before it means anything. Our guide on how to check your own AI search visibility shows how to run the same test for your brand.
People: who does the work?
You are not hiring a logo. You are hiring the few people who will touch your site each month. These questions find out who they are and what they need from you.
| Question | A good answer sounds like | A bad answer sounds like |
|---|---|---|
| 9. Who exactly will work on our account, and can we meet them? | Named roles, the people who will do the work in the pitch, and a clear statement if any of it is subcontracted. | Senior people pitch, and you never hear from them again. |
| 10. What experience do you have in our industry and our markets? | Specific examples in your sector or a close one, and honesty about where they have less experience. | “We work across every industry.” |
| 11. How, and how often, will we hear from you? | A named contact, a fixed rhythm, and a sample of the report you will receive. | “Whenever you need us.” |
| 12. What will you need from us, and how much of our time? | A realistic list: approvals, access, time with your experts for content, and developer time for fixes. | “Nothing at all, we handle everything.” Good B2B content needs your experts. |
Question 12 catches out more agencies than any other. In complex B2B and SaaS categories, the content that wins is built from your team’s knowledge. An agency that needs none of your time is usually planning to write generic content that any competitor could publish. Our article on SEO for complex B2B and SaaS products explains why.
Measurement: how will you know?
Agree what success means before the work starts, not three months in when the report arrives. These four questions set that agreement.
| Question | A good answer sounds like | A bad answer sounds like |
|---|---|---|
| 13. What results do you expect, by when, and how will you measure success? | Ranges with the assumptions behind them, early signs to watch first and business outcomes later, all agreed in writing. | A ranking position by a date, or “page one in 30 days”. |
| 14. Which numbers will you report, and how do they connect to enquiries or revenue? | Qualified enquiries and opportunities by source, joined to your CRM, with rankings and traffic as supporting signals. | Rankings, traffic and a “visibility score”, with no line to your pipeline. |
| 15. How will you tell your effect apart from seasonality and other channels? | Like-for-like date windows, notes on what changed and when, and pages or markets left alone for comparison. | “Traffic went up, so it worked.” |
| 16. How will you report AI search visibility? | A fixed set of buyer questions, asked on a schedule in named engines, with dated screenshots of who was named and cited. | A single score from a tool they can’t explain. |
For question 14, the answer you want joins search activity to the enquiries your sales team accepts. For question 16, remember that Google counts sites shown in its AI features inside the overall web search data in Search Console, so an agency should be able to explain what its AI visibility report adds to that. Our guide to turning AI visibility into qualified enquiries covers the measurement in detail.
Contract: can you leave cleanly?
The contract is where an unhappy year turns into an expensive one. Ask these four before you see the proposal, so the answers shape it.
| Question | A good answer sounds like | A bad answer sounds like |
|---|---|---|
| 17. Who owns our accounts, content and data, and what happens to them if we leave? | You own every account, the content and the data. They are added as users and removed when the work ends. | Accounts set up in the agency’s name, or content that stays theirs. |
| 18. What is the minimum term, and how do we leave? | A short first term or a reasonable notice period, and a written handover of everything they built. | A long lock-in with no break clause and automatic renewal. |
| 19. What exactly is in scope each month, and what costs extra? | Written deliverables, what is excluded, and how changes to scope are agreed. | “A bank of hours”, with no list of what the hours buy. |
| 20. Will you guarantee any rankings or results? | “No. Here is what we expect, why, and how we will both know.” | “Yes, page one guaranteed.” |
Keep the keys yourself
Question 17 has a simple practical test. Google Search Console gives an owner full control of a property, including who else has access, and every property must keep at least one verified owner. Google Analytics lets you add people at account or property level, and adding them at property level limits what they can reach. So keep the owner and administrator roles in your own company’s name, and add the agency as a user. When the work ends, remove them. Google’s help page adds one detail most people miss: when you remove a verified owner, delete their verification tokens too, or they can verify ownership again.
The same applies to your ad accounts, tag manager, hosting and content. If any of it lives in the agency’s name, have it moved before you sign.
Red flags that end the conversation.
A low score on one question can be a misunderstanding. These can’t. If you hear any of them, a high score elsewhere doesn’t make up for it.
- Guaranteed rankings or resultsGoogle says no one can guarantee a first-place ranking. An agency that promises one either doesn’t understand search or doesn’t mind misleading you.
- “Number one agency” claimsUsually from a list the agency wrote or paid for. Perplexity said as much in our own test. Ask who compiled the ranking, and when.
- Secret or proprietary methodsGoogle warns against agencies that are secretive about what they will do. A method you can’t see is a method you can’t check.
- A long lock-in with no exitAn agency confident in its work offers a reasonable notice period. A term you can’t leave protects the agency, not you.
- No access to your own accountsIf you can’t log in to your own analytics, Search Console or ad accounts, you can’t check the report, and you can’t leave without losing your history.
- Numbers without dates or sources“Traffic up 400%” with no tool, no windows and no client is not evidence. Run the three questions from chapter 04.
One more, from Google’s page: be wary of agencies that contact you out of the blue promising results. A cold email is not a red flag on its own, but a cold email with a promise in it usually is.
The agency scorecard.
Name up to three agencies, then score each answer: Good (2), Unclear (1) or Bad (0). Leave a question blank if you didn’t ask it. The totals update as you go, by group and overall. A bad answer on guarantees, ownership or exit is flagged whatever the total. Nothing you enter is sent anywhere.
Score at least ten questions per agency to compare them fairly.
Read the group totals before the overall one. An agency that scores well on method but badly on evidence may be good at explaining and less good at delivering. One that scores well on everything except the contract may be fine, once the contract is fixed. Use the lowest group as your next conversation.
Test the agency before you sign.
Answers in a meeting are cheap; a small piece of real work is not. Before a long engagement, ask each shortlisted agency for something you can judge, such as a short review of one problem on your site or a written plan for the first 90 days. Give each the same brief, so you compare the work, not the pitch.
Look at three things in what comes back. Is it about your business, or could it have been sent to anyone? Does every number carry a source and a date? And does it tell you something you didn’t already know? If you have a brand you suspect is missing from AI answers, our article on why brands go missing from AI shortlists gives you a useful benchmark for that conversation.
Questions owners ask.
What questions should I ask an SEO agency before hiring?
Ask about evidence, method, people, measurement and the contract. Can they show a dated result with its source? What will they do in the first 90 days? Who does the work? How will success be measured against enquiries? Who owns the accounts, and how do you leave? Google’s “Do you need an SEO?” page is a useful starting list.
How do I choose an AI SEO agency?
Ask what they do beyond good SEO, because Google says AI Overviews need no special optimisation. Then ask to see a dated test: the exact question, the engines used, who was named and the screenshots. Choose the agency whose test is repeatable and honest, including about where the agency itself doesn’t appear.
What are the red flags when hiring an SEO agency?
Guaranteed rankings, claims to be number one, secret methods they won’t explain, long contracts with no exit, accounts held in the agency’s name, and numbers without dates or sources. Any one of these outweighs a polished pitch.
How do I vet a GEO agency’s claims about ChatGPT?
Ask for the exact prompt, the date, the engine and its settings, and a screenshot of the answer. AI answers vary by engine and over time, so one good screenshot proves little. A credible agency repeats a fixed set of questions on a schedule and shows you the misses as well as the mentions.
Should an SEO agency own my Search Console or Analytics account?
No. Keep the owner and administrator roles in your company’s name and add the agency as a user. Google’s own guidance suggests giving a new SEO read access to Search Console at first. When the work ends, remove their access and, for Search Console, delete any verification tokens they added.
Sources: Google Search Central, “Do you need an SEO?” and “AI features and your website”; Search Console Help on owners, users and permissions; Google Analytics Help on adding users, all read 7 November 2026. Prolinkage’s own AI search test, ChatGPT, Perplexity and Google AI Overview, 6 November 2026. Client results: FullTilt Team Development, GA4 organic-search key events, 1 May–28 Nov 2024 vs 2 Oct 2023–30 Apr 2024; Clutch verified review, Leopard Project Controls, 3 July 2024 (client-reported).