As we move through the second half of 2026, now is one of the most important times of the year for small business owners in Arizona to review their tax situation. Waiting until December or early 2027 often means missed opportunities and higher tax bills.
At Vault Financials, we work with Phoenix-area businesses every day on mid-year tax planning. This guide outlines the key areas you should review right now to stay compliant and keep more of your hard-earned money.
Why Mid-Year Tax Planning Matters in 2026
Several important federal changes are now fully in effect for 2026. In addition, Arizona has updated its conformity rules. Many business owners set their estimated tax payments earlier in the year based on old assumptions. July and August are the ideal months to true up those numbers before the critical September 15 quarterly payment deadline.
Acting now can help you:
- Avoid underpayment penalties
- Maximize the permanent 20% Qualified Business Income (QBI) deduction
- Take advantage of 100% bonus depreciation and higher Section 179 limits
- Claim valuable Arizona tax credits
- Improve cash flow for the rest of the year
1. Review Your Estimated Tax Payments
Both federal and Arizona estimated taxes are due on the same schedule in 2026:
- April 15, 2026
- June 15, 2026
- September 15, 2026
- January 15, 2027
Arizona also requires estimated payments for the Small Business Income tax if your liability is expected to exceed $1,000. You generally need to pay either 90% of the current year’s tax or 100% of the prior year’s tax.
Action Step: Project your full-year income and expenses under current 2026 rules. Adjust your September 15 payment if needed. This is the single most valuable mid-year move for most business owners.
2. Maximize the Permanent 20% QBI Deduction
The 20% Qualified Business Income deduction is now permanent. Entity structure, reasonable compensation (for S-Corps), and income levels all affect how much you can claim.
3. Take Advantage of Bonus Depreciation and Section 179
100% bonus depreciation is available again. This means you can fully expense many new and used assets in the year you place them in service. Section 179 limits have also increased, giving small businesses more flexibility to write off equipment, vehicles, and software immediately.
4. Arizona-Specific Opportunities
- Charitable Contribution Credits (Form 321) – Dollar-for-dollar Arizona tax credit
- Research & Development Credit
- Pass-Through Entity Tax (PTET) election
5. Common Mistakes We See in Mid-Year Reviews
- Ignoring the September 15 estimated payment deadline
- Not adjusting for higher income later in the year
- Missing Arizona credit opportunities
- Failing to document business expenses properly
- Waiting until tax season to address entity structure issues
What You Should Do Next
- Gather your year-to-date profit & loss statement and balance sheet.
- Project your full-year income and expenses.
- Review estimated tax payments and adjust the September 15 amount if needed.
- Identify any large asset purchases planned for the rest of 2026.
- Look into Arizona charitable and other available credits.
- Schedule a mid-year tax planning meeting with your advisor.
Need Help With Your 2026 Tax Planning?
At Vault Financials, we help Phoenix and Arizona small business owners stay ahead of tax deadlines and opportunities. Whether you run an S-Corp, partnership, sole proprietorship, restaurant, real estate company, or film production business, we can help you create a clear plan for the rest of 2026.
Book a consultation with our team today.
Disclaimer: This article is for educational purposes only and does not constitute tax, legal, or financial advice. Tax laws change and individual situations vary. Please consult a qualified tax professional regarding your specific circumstances.