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We keep you up to date on the latest tax changes and news in the industry.

Important June 2026 Tax Deadlines for Inland Empire Business Owners

As summer starts heating up across Rancho Cucamonga, Upland, and Ontario, it is easy to let tax planning slide to the back burner. But for local small business owners—whether you are managing a bustling medical clinic, closing commercial real estate deals, or running a trucking fleet along the I-10—June brings a few critical tax deadlines that demand your attention.

Keeping your cash flow healthy and avoiding unnecessary IRS penalties requires staying ahead of the curve. Let's break down the key June 2026 tax due dates you need to mark on your calendar.

June 15: Q2 Estimated Tax Payments

For owner-operators in logistics, independent real estate agents, and many private medical practitioners, June 15 is the most important date this month. This is the deadline to submit your second quarter estimated tax payment for the 2026 tax year.

The U.S. tax system operates on a "pay-as-you-earn" basis. While W-2 employees have taxes withheld automatically, self-employed individuals and business owners must make proactive quarterly payments. Missing these prepayments can trigger frustrating underpayment penalties, which are calculated quarterly based on the federal short-term rate plus three percentage points.

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Fortunately, federal tax law provides "safe harbor" rules to help you avoid these penalties. You are generally safe if you pay at least 90% of your current year's tax liability or 100% of the previous year's tax. However, if your Adjusted Gross Income (AGI) exceeded $150,000 last year ($75,000 if married filing separately), that prior-year safe harbor jumps to 110%.

Let's say you run a successful dental practice in Upland and your revenue spiked this year. You need to ensure your Q2 payment accounts for that growth to hit your safe harbor target. If you have questions about adjusting your estimates, now is the time to review your year-to-date numbers.

June 10: Tip Reporting Requirements

If your business model includes tipped employees—such as specific transportation services or niche wellness clinics—June 10 is an essential deadline. Employees who received more than $20 in tips during May must report those earnings to you by this date using IRS Form 4070 or a detailed written statement.

As the employer, you are responsible for withholding FICA and income taxes on these tips from their regular wages. If their standard wages cannot cover the withholding, you will need to report the uncollected amount in box 8 of their year-end W-2. The employee will then pay the uncollected withholding when filing their annual return.

Southern California Small Business Owners: Let’s Optimize Your Tax Strategy
Are you a small business owner in Inland Empire, Los Angeles, or Orange County? Let’s discuss tailored tax strategies designed specifically for small businesses in Southern California. Book your free consultation with a licensed CPA today.
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June 1: Form 5498 and IRA Valuations

Early in the month, June 1 serves as the final due date for IRA trustees to issue Form 5498. This form provides the fair market value (FMV) of IRA accounts as of December 31, 2025.

Why does this matter? For our clients actively planning for retirement or managing inherited accounts, this December 31 valuation determines the required minimum distributions (RMDs) you must take if you are age 73 or older during 2026.

Exceptions: Overseas Taxpayers and Disaster Relief

Not everyone falls under the standard filing deadlines. If you are a U.S. citizen living and working abroad, June 15 is your deadline to file your 2025 income tax return and pay any taxes due. (For those affected by the terrorist attacks in Israel, the IRS has extended this deadline to September 30, 2026). Military personnel serving in combat zones receive an automatic 180-day extension following their deployment.

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Additionally, here in Southern California, we are no strangers to natural disasters like wildfires or severe storms. When a region is officially declared a disaster area, the IRS routinely extends filing and payment deadlines. If a due date happens to fall on a weekend or a legal holiday, it automatically rolls over to the next business day. For the latest updates on regional relief, you can check these official resources:

Keep Your Inland Empire Business on Track This Summer

Mid-year tax planning is what separates thriving Inland Empire businesses from those struggling with cash flow surprises at year-end. Whether you need to adjust your estimated payments after a lucrative real estate closing or need help structuring your logistics fleet's bookkeeping, we are here to help. Reach out to our office today to schedule a consultation and ensure your tax strategy is perfectly aligned for the rest of 2026.

Southern California Small Business Owners: Let’s Optimize Your Tax Strategy
Are you a small business owner in Inland Empire, Los Angeles, or Orange County? Let’s discuss tailored tax strategies designed specifically for small businesses in Southern California. Book your free consultation with a licensed CPA today.
Book Your Appointment
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