How to File California Sales Tax Online

Filing your California sales tax return is simple with the state’s online system. You can file and pay directly through the CDTFA Online Services, as long as your business is registered to collect and remit sales tax.

This guide walks you through the step-by-step process of filing online so you can submit returns on time, avoid penalties, and stay compliant with California’s sales tax rules.

What You Need Before Filing

Before you start your California sales tax return, it’s important to gather the right information so your filing is accurate and complete. Here are the standard items you should have ready:

• California Seller’s Permit or Sales and Use Tax Account Number: This is your official identification number issued by the CDTFA. You’ll need it to log in and file your return.
• CDTFA Online Services Login: Make sure you have your username and password ready for the CDTFA Online Services Portal. If you haven’t set this up yet, you’ll need to register first before filing.
• Total Sales for the Filing Period: Collect records of all your gross sales from every channel, including Shopify, Amazon, in-person sales, and other platforms. California requires you to report all sales, not just taxable ones.
• Taxable and Nontaxable Sales: Break down your sales into taxable and exempt categories. It ensures you only pay tax on what’s required and that you can properly claim exemptions.
• Purchase Records (if applicable): If your business made purchases without paying sales tax at the time of sale, you’ll need those figures to calculate use tax.
• Local District Tax Information: California has multiple district tax rates that vary by city and county. Be prepared to report sales by location if you made taxable sales in a district where you are engaged in business. For many companies, this means reporting sales from their place of business; for businesses with sales exceeding a certain economic nexus threshold, it may apply to all districts statewide.
• Payment Method: Have your bank account and routing number ready if you plan to pay online through the CDTFA system.
• Filing Frequency: The CDTFA assigns you a filing schedule; monthly, quarterly, or annually, based on your business activity. You can confirm your assigned frequency on your CDTFA registration documents or through your online account.

By preparing these details in advance, you’ll save time and reduce the risk of errors when filing through CDTFA Online Services. 

Step-by-Step: How to File California Sales Tax Online

The online filing process is a logical progression of data entry and verification. While the exact screen layouts may evolve with the new eServices platform, the core workflow remains constant.

Step 1. Prepare your Shopify Sales Tax Report. Gather all your sales data, including total, taxable, and exempt sales, from your ecommerce platforms and POS systems.

Step 2. Go to the CDTFA Online Services website.

Step 3. Log in using your username and password from the 1Password vault. Check your shared email or phone number and input the OTP when applicable.

Step 4. Click the “Sales and Use Tax” hyperlink on the dashboard.

Step 5. Click “File Return” next to the filing period you want to process.

Step 6. Select the applicable option (such as a regular or amended return), then click Next.

Step 7. Enter your Total Sales amount for the period, then click Next.

Step 8. Enter any Additional Sales details if applicable, then click Next.

Step 9. Select and click the applicable options (e.g., deductions, exemptions, or adjustments), then click Next.

Step 10. Enter County Sales information based on your Shopify Sales Tax Report, then click Next.

Step 11. Update your Tax Jurisdiction data as required, then click Next.

Step 12. Select the applicable option for excess tax or additional adjustments, then click Next.

Step 13. Enter any Excess Tax Collected during the period, then click Next.

Step 14. Review all balances carefully, verify that they match your Shopify report, then click Next.

Step 15. Fill out the Preparer Information (name, title, and contact details) and click Submit.

Step 16. Save the confirmation in your preferred location for recordkeeping purposes. Keeping online records using Google Drive is a common option.

Helpful tip: You can always click “Save and Submit Later” to avoid losing progress during interruptions such as internet issues or CDTFA system downtime.

Due Dates

FREQUENCY	REQUIREMENT	REPORTING PERIOD	DUE DATE
Monthly	Standard assignment for most sellers	Each month	Last day of the following month (e.g., Jan return due Feb 28/29).
Quarterly	Default for many small to mid-sized businesses	Q1: Jan–Mar Q2: Apr–Jun Q3: Jul–Sep Q4: Oct–Dec	April 30, July 31, October 31, and January 31 of the following year.
Annual	Assigned by CDTFA based on very low sales volume	January – December	January 31

The California Department of Tax and Fee Administration (CDTFA) assigns your filing frequency when you register, based on your sales volume. Your return due dates depend on that frequency:

• Monthly Filers Returns are due on the last day of the month following the reporting month. Example: June’s return is due July 31.
• Quarterly Filers (most common for small and mid-sized sellers)
  • Q1 (Jan–Mar): Due April 30
  • Q2 (Apr–Jun): Due July 31
  • Q3 (Jul–Sep): Due October 31
  • Q4 (Oct–Dec): Due January 31
• Quarterly Prepay Filers (for higher-volume sellers assigned this schedule) Two prepayments are required each quarter, with the full quarterly return due at the end of the following month (on the same dates as the quarterly returns above).
• Yearly Filers (Sales Tax Accounts) Returns covering Jan–Dec are due January 31 of the following year.
• Fiscal Yearly Filers Returns covering June and July are due on July 31.

Important: If your due date falls on a weekend or a California state holiday, the deadline is extended to the next business day.

Timely Filing Discount

Some states give businesses a discount for collecting, filing, and remitting sales tax on time. Currently, California does not offer any timely filing discount.

Filing Amended Returns

If you discover an error on a previously filed return, file an amended return and pay any additional tax, penalty, or interest due. You can use the CDTFA Interest Rate Calculator to estimate interest.

If your correction results in a refund, CDTFA automatically treats it as a claim for refund, no separate filing needed. 

1. Log in to CDTFA Online Services.
2. Go to your account and select the filing period to amend.
3. Under I Want To, choose File, Amend, or Print a Return/Report, then click Amend Return.
4. Update your figures, follow the prompts, and submit.

Note: CDTFA applies previous payments to your amended filing and automatically adjusts penalties or interest.

Refunds

If you overpaid California sales or use tax, you can request a refund online through CDTFA Online Services or by mailing Form CDTFA-101 with supporting documents to: Refunds Section, MIC:39, PO Box 942879, Sacramento, CA 94279-0039.

Claims must be filed within three years of the return’s due date or six months from the date of overpayment, whichever is later.

For refunds on vehicle use tax paid at the DMV, verify your tax rate on CDTFA’s website and submit Form CDTFA-101-DMV to the Consumer Use Tax Section, MIC:37, PO Box 942879, Sacramento, CA 94279-0037.

Other Filing Methods in California

If you’re having difficulty filing your California sales tax return online, you can try the following options:

• File with TaxHero – Let expert accountants in TaxHero prepare your sales tax returns for you. We’ll take everything off your hands so that you can spend your time more efficiently managing your business.
• By Mail: Complete a paper return (Form CDTFA-401-A) and mail it with a check or money order payable to “California Department of Tax and Fee Administration.”
• In Person: Visit a local CDTFA office for filing and payment assistance.

Let TaxHero Manage Your California Sales Tax Returns

TaxHero doesn’t just handle your California sales tax return, we manage filings across every state where your business has nexus, ensuring each return is filed accurately and on time at the frequency required.

This means you stay compliant nationwide without having to track multiple rules and deadlines yourself.

Don’t wait until the next deadline, schedule your demo today!