An SEO firm sells a service whose entire rulebook is public: the search engines document what they reward, what they penalise, and even what questions to ask the firms themselves. That is unusual among professional services, and it hands buyers real power, because every material claim in a pitch can be checked against published documentation and the firm's own visible footprint before any contract is signed. What a firm legitimately adds is craft, capacity and judgement in applying that public guidance. This page covers what the work actually consists of, the vetting Google itself recommends, and the red flags its documentation names outright.
What the work actually is
Strip the packaging and an SEO firm does four things. It makes a site crawlable and technically sound, because Google finds pages primarily through links from pages it already knows and needs access to the same resources users see. It produces or improves content, against a published standard: helpful, easy to read, well organised, original, current and demonstrating expertise. It builds structure: titles that are unique and accurately describe each page, descriptive internal links, sensible architecture. And it measures, honestly, over the timeline the documentation itself sets out: changes can take from a few hours to several months to be reflected in search results. Everything else in a proposal is either one of these four in better clothes, or something to question.
The interview Google recommends
Google's guide to hiring an SEO reads like a buyer's checklist. Ask for examples of previous work and success stories. Ask whether the firm follows Google's published guidelines, and note that good firms support their recommendations with official documentation. Ask what results they expect, how they will measure them, and over what timeframe. Ask about experience in your industry and your kind of market, and whether they will explain what they do in plain language. The pattern across every question is transparency: a firm that answers all of them specifically, with named clients and checkable outcomes, has effectively done your due diligence for you. A firm that answers any of them with mystique has answered all of them.
The red flags, from the platform itself
The same guidance names what should end a conversation: no one can guarantee a #1 ranking on Google, so guaranteed rankings are disqualifying; so are claimed special relationships with Google or priority submission, secretiveness about methods, unsolicited email pitches, and link schemes. Google's spam policies extend the list to method: buying or selling links for ranking purposes, keyword stuffing, cloaking, doorway pages, and scaled content abuse, generating many pages without adding value, all carry consequences up to not appearing in results at all. The practical use of both lists is preventive: read any proposal against them, and ask the firm directly how links are earned and how content is produced. The risk of a bad answer lands on your domain, not the firm's.
Judging the firm by its own footprint
The least fakeable evidence costs nothing to check. Search the phrases an SEO firm would want to rank for and see where it appears; a firm invisible for its own trade is selling what it has not demonstrated on the one site it fully controls. Read its case studies for named clients, dated results and specific query families rather than anonymised percentage charts. Look for printed pricing, a published team and a verifiable address. This index applies exactly that standard: firms are listed on what they publish about themselves and what can be verified from their own pages, never on pay-for-placement, so the shortlist you build here starts from evidence rather than from whoever pitched you last.
Questions people ask about seo firm
What does an SEO firm actually deliver each month?
Technical site work, content production or improvement against Google's published standards, structural work on titles and internal links, and measurement. A credible retainer itemises all four; a vague one is billing for the packaging.
How do I quickly screen an SEO firm?
Search the phrases it sells and see if it ranks; read its case studies for named clients and dated outcomes; ask Google's recommended interview questions; and reject guaranteed rankings outright, since Google states no one can guarantee a #1 position.
Can a firm's methods get my site penalised?
Yes. Google's spam policies name purchased links, keyword stuffing, cloaking, doorway pages and mass-generated low-value content, with consequences up to removal from results. Ask any firm how its links are earned and its content reviewed before signing.
How long until an SEO firm's work shows results?
Google's documentation says individual changes take anywhere from a few hours to several months to be reflected, and recommends allowing a few weeks just to assess a change. Structure the engagement around interim milestones rather than a promised date.