A single-location business never has to think about this question. A business that's grown to two or more physical locations, or that serves multiple distinct service areas, has to get the structure right, because Google Business Profile is built around one profile per physical or service location, not one profile per business.
The basic rule
If a business has genuinely separate, staffed locations (a second office, a second storefront), each one gets its own profile, with its own accurate address and phone number specific to that location. Combining two real locations into a single profile misrepresents both.
Service-area businesses are different
A business that travels to customers rather than operating from a public-facing storefront (many home service trades) can typically set up as a service-area business on a single profile, defining the areas served without needing a separate profile for each town, as long as there's genuinely one operating base.
Don't create a location profile just to rank in another city
Creating a profile for a location that isn't a real, staffed address, specifically to try to rank in a nearby city's search results, violates Google's guidelines and is a common, easily flagged violation. See Google Business Profile suspensions: common causes and how to avoid them.
Managing multiple profiles
Google's Business Profile Manager supports managing several locations under one account, which keeps them organized without merging their individual identities, reviews, or search presence.
Keep information consistent across locations, but accurate to each
Each location's profile should reflect that location's actual hours, phone number, and services, even if the overall brand and general offerings are the same across all of them.
Questions
What if I have one legal business but genuinely serve three separate cities from three separate offices?
Each staffed office location gets its own profile, since each is a genuine physical presence that customers can be directed to.
Can reviews be shared across multiple location profiles?
No, reviews are tied to the specific location profile they were left on. This is part of why the physical location structure matters from the start.
What if I close one location?
Google allows marking a location as permanently closed rather than simply deleting the profile, which preserves its history accurately rather than leaving stale information active.