Choosing your Google My Business listing’s primary category is one of the most important sections you will need to fill out. With so many choices, the primary category you choose might not be so obvious.
For example, let’s say you are a law firm that handles Family Law cases but your goal is to really focus on Divorce cases. Well, Family Law Attorney is a Primary Category and so is Divorce Lawyer. You are in luck, since Divorce Lawyer is an option, set this as your Primary Category, and you are set.
Now, let’s take a different example. You are a law firm that handles Personal Injury cases but your goal is to really focus on Car Accident cases. Well, Personal Injury Attorney is a category but Car Accident Lawyer is not a category in Google My Business. How do you know which is the best category to choose? You want to take the keyword you wish Google My Business had as an option and do a Google Map search. The search results for Car Accident Attorney brings up a large handful of listings using Personal injury Attorney as their primary category. Some listings might also say Attorney or Law Firm. To choose the best category, its best to go with what the majority is going with. In this scenario, it’s going to be the category Personal injury Attorney. You also want to avoid general categories for your primary category if possible. Options such as Law Firm or Attorney are too general and will display your listing to people looking for a lawyer but not necessarily a personal injury attorney.
As per Google Guidelines, categories are used to describe your business and connect you to customers searching for the services you offer. Choose a primary category that describes your whole business. Be as specific as possible. Choose Nail Salon instead of Salon. Keep in mind that you can not create your own category. If the category you had in mind isn’t available, choose the next best category that describes your business. Be aware, once you choose a primary category, if you try and change it, you may be asked to re-verify your listing.
https://support.google.com/business/answer/7249669?hl=en