The SEO agency market ranges from excellent to actively harmful, and the difference isn't always obvious from a sales pitch alone. A structured vetting process protects against wasted money and, in worse cases, tactics that can damage a site's standing.
Guaranteed rankings. No legitimate agency can guarantee a specific ranking position — Google's algorithm isn't something any outside agency fully controls, and a guarantee is a reliable sign of either naivety or dishonesty.
Prices that seem too good to be true. Extremely cheap SEO services often rely on low-quality tactics — spammy backlinks, thin AI-generated content — that can actively harm a site over time rather than helping it.
Vague or evasive answers about methodology. A legitimate agency should be able to clearly explain what they do, in specific terms, instead of relying on vague buzzwords without substance behind them.
A credible agency should be able to walk through their process concretely — how they conduct research, what content and technical work actually looks like, and how they measure and report progress — rather than offering only generic assurances.
Ask for specific examples of past client results, ideally with the ability to speak directly with a current or former client about their genuine experience, not just curated testimonials selected by the agency itself.
Ask specifically what metrics they report on and how often — an agency reporting only on vanity metrics (like keyword rankings for easy, low-value terms) without connecting work to genuine business outcomes (traffic, leads, revenue) is a meaningful warning sign worth probing further.
Understand contract length, cancellation terms, and what happens to work already completed (content, technical fixes) if the relationship ends — agencies requiring unusually long lock-in contracts with limited flexibility deserve extra scrutiny before committing.
Beyond technical competence, genuine communication style and cultural fit matter for what's typically a long-term relationship — an agency that's technically strong but difficult to communicate with regularly can still be a poor practical fit.
What specific tactics will be used to improve rankings? How will progress be measured and reported? Can you provide references from clients in a similar industry or of similar size? What happens if results don't materialize as expected within a reasonable timeframe?
Choosing an SEO agency well means watching for clear red flags (guaranteed rankings, suspiciously low prices), asking specific questions about actual process and past results, and evaluating genuine communication fit alongside technical competence. The time invested in careful vetting upfront protects against a far more costly mistake of a poor agency relationship discovered only after months of wasted spend.
Specialization matters as much as general competence: an agency with deep experience in local service businesses may not be the right fit for a SaaS company competing on highly technical, national keywords, and vice versa. Asking directly about experience with businesses of a similar model and scale, not just the same industry, often reveals more about actual fit than industry experience alone.
The proposal or initial audit an agency provides during the sales process is itself a useful evaluation tool: a generic, templated audit that could apply to almost any website suggests a templated approach to the actual work, while a proposal referencing specific, verifiable issues on the actual site under discussion suggests the agency did real diligence before ever asking for a signature.