Publication 109, Internet Sales
Additional Information

For additional information or assistance, please take advantage of the resources listed below.

Customer Service Center

1-800-400-7115 (TTY:711)

Customer service representatives are available Monday through Friday from 7:30 a.m. to 5:00 p.m. (Pacific time), except state holidays. In addition to English, assistance is available in other languages.

Offices

Please visit Office Locations & Addresses for a complete listing of our office locations.

You can find additional law and policy-related information that will help you understand how the law applies to your business, within the Business Taxes Law Guide and Guidelines/Manuals – Sales & Use Tax and Special Taxes and Fees.

You can also verify seller’s permit numbers (see Verify a Permit, License, or Account).

Multilingual versions of publications are available (see Forms & Publications).

Another good resource—especially for starting businesses—is the California Tax Service Center.

Tax Information Bulletin

The quarterly Tax Information Bulletin (TIB) includes articles on the application of law to specific types of transactions, announcements about new and revised publications, and other articles of interest. Sign up for our CDTFA Updates email list and receive notification when the latest issue of the TIB has been posted.

Free Classes and Seminars

We offer free online basic sales and use tax classes, including a tutorial on how to file your tax returns. Some classes are offered in multiple languages.

Written Tax Advice

For your protection, it is best to get tax advice in writing. You may be relieved of tax, penalty, or interest charges that are due on a transaction if we determine that we gave you incorrect written advice regarding the transaction and that you reasonably relied on that advice in failing to pay the proper amount of tax. For this relief to apply, a request for advice must be in writing, identify the taxpayer to whom the advice applies, and fully describe the facts and circumstances of the transaction.

For written advice on general tax and fee information, please visit our General, Non-Confidential Tax Questions Form to email your request.

You may also send your request in a letter. For general sales and use tax information, including the California Lumber Products Assessment or Prepaid Mobile Telephony Services (MTS) Surcharge, send your request to:

Audit and Information Section, MIC:44
California Department of Tax and Fee Administration
PO Box 942879
Sacramento, CA 94279-0044

For written advice on all other special tax and fee programs, send your request to:

Program Administration Branch MIC:31
California Department of Tax and Fee Administration
PO Box 942879
Sacramento, CA 94279-0031

Taxpayers’ Rights Advocate

If you would like to know more about your rights as a taxpayer or if you have not been able to resolve a problem through normal channels (for example, by speaking to a supervisor), see publication 70, Understanding Your Rights as a California Taxpayer, or contact the Taxpayers’ Rights Advocate Office for help at 1-888-324-2798. Their fax number is 1-916-323-3319.

If you prefer, you can write to:

Taxpayers’ Rights Advocate, MIC:70
California Department of Tax and Fee Administration
PO Box 942879
Sacramento, CA 94279-0070

Regulations

Publications

Tax and Fee Guides

Revision July 2026