Tax Deadlines California Business Owners Can’t Afford to Miss

Running a business in California isn’t just about building a great team and serving your customers. It’s also about staying ahead of the IRS and Franchise Tax Board (FTB) calendar. Miss one deadline and you could end up with painful penalties — the FTB charges 5% of unpaid taxes per month (up to 25%), plus interest that quietly chips away at your bottom line.⁽¹⁾

That’s why I’ve put together this quick 2025 Burbank business tax calendar. It covers everything you need to know — from federal and California state filing dates to quarterly payments and payroll taxes. And here’s a reality check: with interest rates higher this year (IRS underpayment rate at 7%, FTB at 8%), missing a deadline is more expensive than ever.⁽²⁾

With the right planning, you can stay compliant, skip the penalties, and focus on what you actually enjoy — growing your business.

Key Federal Tax Dates for 2025

Date (2025)	Obligation
Jan 31	Forms 1099-NEC & W-2s due to contractors/employees (and to the IRS when required).⁽³⁾
Apr 15	Individual (Form 1040) & most corporate (1120) returns due — file or request an extension. (If April 15 falls on a weekend/holiday, the due date moves to the next business day.)
Jun 16	Q2 estimated tax payment due for calendar-year taxpayers — (standard date is June 15, but in 2025 the 15th is a Sunday so it moves to Monday, June 16).
Sep 15	S-Corp & partnership returns (or extended returns) due for calendar-year filers (Form 1065, Form 1120-S deadlines / extension windows). Use Form 7004 to request extensions where appropriate. ⁽⁴⁾
Oct 15	Final filing deadline for individual returns that received an extension (Form 1040 with Form 4868 filed).

👉Pro tip: The IRS starts processing returns on Jan 27, 2025, so file early if you can. Refunds move faster when you’re first in line. In 2024, the average refund was around $3,000 to $3,100, so it’s worth getting your paperwork in early.

Key California Franchise Tax Board (FTB) Deadlines

California’s deadlines hit differently because even when you get an extension, you still have to pay on time. Here are the big ones to keep on your radar:

Date (2025)	Form / Requirement	Who Needs It / Notes
Mar 15	Form 100S – S-Corporation Franchise / Income Tax Return	S-Corps: for calendar-year filers, the return and any tax due must be submitted. California grants an automatic extension, but that extension is to file, not to pay.
Apr 15	Form 100 / 100S for C or S Corporations (calendar-year)	C-Corps file by this date for returns and payments. Minimum franchise tax (often $800) applies even if there’s no profit.
Also Apr 15	Form 568 – LLC Return of Income	For LLCs taxed as partnerships or disregarded entities, or LLCs otherwise required to file; note: extensions exist, but payments/taxes are due on the original deadline.
15th day of the 4th month of the tax year	Form 3522 – LLC Annual Franchise Tax Voucher ($800 minimum tax)	ALL California LLCs must pay this minimum tax, regardless of income or business activity. New since 2024, exemption for the first year (under AB85) expired, so this applies even in Year One.

Quarterly Estimated Tax Deadlines

If you expect to owe $1,000 or more in federal taxes (after withholdings and credits), you need to make estimated payments. California’s threshold is lower — $500 if you file jointly, $250 if married/RDP filing separately.

Due Date	Payment Period Covered	Forms to Use
Apr 15, 2025	Jan 1 – Mar 31, 2025	IRS Form 1040-ES, California FTB Form 540-ES
Jun 16, 2025	Apr 1 – May 31, 2025 (June 15 falls on Sunday)	1040-ES / 540-ES
Sep 15, 2025	Jun 1 – Aug 31, 2025	1040-ES / 540-ES
Jan 15, 2026	Sep 1 – Dec 31, 2025	1040-ES / 540-ES

💡 Pro tip: Most California business owners use the safe harbor method — pay at least 100% of last year’s total tax (110% if your AGI is over $150,000) to skip underpayment penalties. If your income fluctuates, the annualized income method (IRS Pub 505) can help you stay accurate without overpaying.

Payroll & Sales Tax Filing Deadlines

Payroll and sales tax filings are the backbone of compliance in California — and also the most common source of late penalties. Here’s a quick overview:

Payroll Taxes

Federal (IRS):
Most employers file Form 941 quarterly to report federal income tax, Social Security, and Medicare withholdings. Smaller employers with under $1,000 in total liability can use Form 944 annually.⁽⁵⁾
Your deposit schedule (monthly or semiweekly) depends on your lookback period — if you paid over $50,000 in payroll taxes, you’re a semiweekly depositor. And if you ever hit $100,000 in tax on a single day, you must deposit it the next business day.
Miss a deposit? IRS penalties range from 2% to 15%, depending on how late you are.
California (EDD):
At the state level, file DE-9 and DE-9C quarterly to report wages and payroll taxes. California requires e-filing and e-payments, and skipping either can trigger penalties — including $20 per employee for late wage reports, plus fines for missing e-filing.

Sales Tax (CDTFA)

The California Department of Tax and Fee Administration (CDTFA) decides your filing frequency — monthly, quarterly, or annually — based on your sales volume. Deadlines are strict, and interest begins the day after you miss a payment.

Don’t Overlook New Hire Reporting

If you hire employees, report them to the New Employee Registry within 20 days of their first day. Forgetting to do this can cost you about $24 per employee, and the fine is even higher if it looks intentional. It’s a tiny task, but it’s one that payroll auditors always check.

How to Avoid Missed Deadlines

Let’s be real — tax deadlines aren’t fun, but missing one can hit your cash flow hard. Here’s what I tell my clients: build small, consistent habits that make staying compliant automatic.

1. Set reminders that actually work.
Add every filing date to your calendar with two alerts: one two weeks before, and another a few days before the deadline.

2. Automate as much as possible.
Tools like Gusto or QuickBooks handle payroll taxes and deposits automatically — some even offer penalty protection if anything slips.

3. Pay online, every time.
Use EFTPS for the IRS and Web Pay for California’s FTB. You get a digital record and peace of mind.

4. Have two sets of eyes on everything.
If you have a team, don’t let one person manage all filings alone. A quick review can catch expensive mistakes.

5. Reconcile monthly.
Take 30 minutes each month to match payroll entries with bank transactions. It’s much easier to fix a $200 issue now than a $2,000 mess later.

6. Keep a small “tax cushion.”
Set aside funds for taxes so cash flow hiccups don’t turn into missed payments.

7. Call in a pro when things get busy.
A good CPA or tax professional can save you more time (and money) than you might think.

Conclusion

Staying ahead of California’s tax deadlines isn’t just about checking boxes — it’s about protecting your profits and peace of mind. One missed payment can trigger penalties that snowball fast.

At America Tax Group, we help Burbank business owners keep every IRS and FTB deadline under control. From payroll filings to estimated payments, we handle the details so you can focus on what matters most — running your business.

👉 Don’t leave compliance to chance. Reach out today and let’s make your 2025 filing season smooth, stress-free, and penalty-proof.

FAQs

1. What happens if I miss a tax deadline in CA?
You’ll face penalties, interest, and late filing fees from the IRS or FTB.

2. Are extensions automatic?
Federal extensions are automatic with Form 4868, and California generally follows. But remember—payments are still due by the original deadline.

3. Can I pay taxes online in California?
Yes, via FTB Web Pay or your MyFTB account.

4. How can I simplify this for next year?
Use a master spreadsheet or client portal that tracks deadlines and sends reminders.