Business FAQs

What are business license requirements?
How do I report a possible code violation?
Where is the Chamber of Commerce located?
Do I have to pay business taxes?

Q: What are business license requirements?
A: All individuals and businesses doing work within city limits, whether or not they have a physical structure in the city, are required to have a business license. This includes contractors, internet and home-based businesses. Applications and renewals are processed at City Hall. Basic business license fee is $11 per year. Licenses requiring a one-time zoning clearance are $52.72, and an additional fee of $300 per individual requiring a background check as described below. All fees are due when application is submitted and are non-refundable and non-transferable.

Contact Information
Planning Division

Q: How do I report a possible code violation?

The City of Diamond Bar's Neighborhood Improvement and Building and Safety Division inspects all structures suspected of code violations to insure compliance, and it directs the code enforcement staff to issue notices of violation to owners. Structures may be in violation due to a number of reasons including building without permits, poor structural integrity, unsafe property site conditions, and the open storage of junk. If a violation is detected, a letter will be sent to the property owner requesting compliance so that fines and/or criminal punishment can be avoided.

If you wish to report a possible code violation, you may send an email to

Q: Where is the Chamber of Commerce located?
A: The Regional Chamber of Commerce of San Gabriel Valley is an independent, non-profit organization created to support the business interests of the community, and to provide business-related services and information to the residents and visitors of eastern San Gabriel Valley. Offices are open between 8am and 5pm Monday through Friday and are located at 19720 E. Walnut Drive South, Walnut, CA 91789.

For more information about services and programs that the Chamber of Commerce offers, please call 909.869.0701.
Q: Do I have to pay business taxes?
A: The State of California has many filing requirements that business owners should be know about. Contact the California State Board of Equalization for details at 800.400.7115.

Business owners have federal tax obligations to comply with, as well. Additionally, all businesses declared as either a partnership or a corporation are required to apply for a Federal Employee Identification Number, even if the business has no employees. The Internal Revenue Service will provide you with free information to help you start a new business when you register for this number. Contact the U.S. Internal Revenue Service for details at 800.829.4477 for recorded information, or at 800. 829.1040 for assistance.