Running a business from home in Contra Costa County

Each rule below links to the section of the Contra Costa County Municipal Code it was read from, with the code text one click away (checked October 2026). General information, not legal advice.

What Contra Costa County's code says

Contra Costa County code What Contra Costa County's code adds
Space used	No more than 1 room or 20% of the floor area, whichever is greater. Applies: A home occupation carried out entirely inside a home. § 82-40.012 · code text No more than one room, or twenty percent of the floor area, whichever is greater, may be used for the home occupation.
Customer visits	Only 1 student may be present at one time. Applies: Students who come for individual instruction at the home. § 82-40.012 · code text If student visits occur, only one student may be present at one time, no more than six student visits may occur per day, and students may be present only between eight a.m. and six p.m. No more than 6 student visits per day. Applies: Students who come for individual instruction at the home. § 82-40.012 · code text If student visits occur, only one student may be present at one time, no more than six student visits may occur per day, and students may be present only between eight a.m. and six p.m. No clients or customers may come to the home business. Applies: The general rule. Students who come for individual instruction are the exception. § 82-40.012 · code text No clients or customers are permitted at the site of the home occupation, except for students engaged in individual home instruction.
Employees	Only the people who live in the home may take part in the business. Applies: The general rule, except where state law provides otherwise. § 82-40.012 · code text Only the residents of the dwelling unit may be involved in the conduct of the home occupation, except as otherwise provided by state law.
Permit	A home occupation permit is required. Applies: The county approves it ministerially, only when the business meets the standards. § 82-40.012 · code text An application for a home occupation permit will be ministerially approved only if it complies with the following standards in addition to the standards specified in Section 82-40.010: A land use permit is required. Applies: When any part of the home business takes place outdoors. § 82-40.014 · code text A land use permit is required for a home occupation if any of the following occur: (1) Any portion of the home occupation activity is conducted outdoors. A land use permit is required. Applies: When the business takes place in an accessory building that meets the accessory structure setback rules. § 82-40.014 · code text (2) The home occupation is conducted within an accessory building that complies with accessory structure setback requirements. A land use permit is required. Applies: When 1 or more employees of the business do not live in the home. § 82-40.014 · code text (3) One or more employees of the home occupation are not residents of the dwelling unit. A land use permit is required. Applies: When more than 1 student is present at a time, or there are more than 6 student visits per day. § 82-40.014 · code text (3) The number of student visits exceeds the amounts specified in subsection (c) of section 82-4.012. A land use permit is required. Applies: When 2 or more business vehicles are used or kept at the home. § 82-40.014 · code text (4) Two or more business-related vehicles are used or kept at the site of the home occupation.

Who this affects

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Frequently asked questions

Can I run a business from my home in Contra Costa County?

County code: home businesses are limited to one room or 20% of floor area, whichever is greater, with no clients and only resident workers.

Running a business from home in Contra Costa County

Key points

What Contra Costa County's code says

Who this affects

Frequently asked questions

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