Your primary category matters most
Google uses your primary category heavily to decide which searches your business shows up for. Choose the single most accurate category for your core service — not the broadest one, and not one you think sounds more appealing.
Choosing an inaccurate category to appear in more searches (a nail salon listing itself as a "spa" for broader reach, for example) typically backfires — it can dilute your relevance for the searches that actually matter for your real business.
Secondary categories add reach without diluting your primary
You can add secondary categories for genuine additional services you offer (a hair salon that also does esthetics, for example) — this is different from choosing an inaccurate primary category, since it reflects real services.
Be as specific as Google allows
Google generally offers specific category options ("Nail Salon" rather than just "Beauty Salon") — use the most specific accurate option available rather than defaulting to a broad, generic one.
Periodically review Google's available category list — new, more specific categories are added over time, and a more precise option may become available after your initial setup.
Frequently asked questions
How many secondary categories should I add? Add genuine ones that reflect real services, not every category that's tangentially related — an overly broad category list can dilute relevance rather than help it.
Can I change my category later? Yes — categories can be updated at any time through your profile settings if your services change or you realize a more accurate option exists.