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When are California sales tax returns due?

Your California sales tax due dates depend on the filing frequency assigned by the California Department of Tax and Fee Administration. The CDTFA bases this on your average monthly tax liability, so businesses with higher sales volume file more frequently.

Quarterly filing is the most common for small businesses. The deadlines are the last day of the month following each quarter. First quarter covering January through March is due April 30. Second quarter covering April through June is due July 31. Third quarter covering July through September is due October 31. Fourth quarter covering October through December is due January 31.

Monthly filers have returns due on the last day of the following month. January sales are due February 28 or 29. February sales are due March 31. This pattern continues throughout the year. The CDTFA typically assigns monthly filing when your average monthly tax liability exceeds $10,000.

Annual filing is reserved for businesses with very low sales tax liability. The annual return covering the full calendar year is due January 31 of the following year. If you’re a new business, the CDTFA may start you on quarterly filing and adjust later based on your actual sales volume.

When a due date falls on a weekend or California state holiday, the deadline extends to the next business day. Keep in mind that “due” means both filed and paid by that date. Filing on time but paying late still triggers penalties.

Late filing penalties start at 10% of the unpaid tax amount. Interest accrues from the original due date until you pay. Repeated late filings can result in your seller’s permit being suspended, which means you cannot legally make sales in California until it’s reinstated. The penalties add up quickly, so missing deadlines gets expensive.

All returns must be filed electronically through the CDTFA’s online portal. Paper filing is no longer accepted for most businesses. You can set up automatic payments if you want to avoid accidentally missing a deadline, though you’ll still need to file the actual return.

If keeping track of filing deadlines and making sure returns are accurate sounds like more than you want to handle, sales tax compliance services can take it off your plate. Your time is probably better spent running your business than tracking quarterly deadlines and navigating the CDTFA portal.

District taxes in California add another layer of complexity. The state rate is 7.25%, but most areas have additional district taxes that push the effective rate higher. San Diego County rates vary by city. Getting the rate wrong on your return creates problems, so double check that your accounting system has the correct rates for where you’re making sales. A San Diego payroll service that also handles bookkeeping can help ensure your sales tax records stay accurate alongside your other financial obligations.

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