Calculate state estimated tax

[amt_blues]

I'm running TurboTax Premier on a PC desktop. I calculated the Federal estimated tax to reflect a significant increase in my 2026 income. How can I do this with my state estimated tax? Thanks.

[TomK2023 · Accepted solution]

You have several options to calculate and print State vouchers for a projected 2026 income increase (similar to your Federal return).

Option 1...

1. Open or continue your return.
2. Under State Taxes tab, Continue through the interview until you reach "A few things before we wrap up [State Name]" or "Other Forms".
3. Look for Estimated Taxes or 2026 Estimated Tax Vouchers.  When you say YES (to prepare vouchers), the program should offer an option to "adjust" or "enter" your 2026 expected income.
4. Enter the same increased income figures you used for your Federal 1040-ES calculation.

Option 2...

1. Open or continue your return.
2. Click on Forms Mode (top right).
3. Scroll down to your State section (left-hand column), and Look for a form labeled [State] Est Tax or Estimated Tax Worksheet (e.g., in CA it's "Form 540-ES").
4. Open that worksheet, and Look for a section titled "2026 Estimated Tax Options".
5. Select the option to calculate based on estimated 2026 income rather than 100% of 2025 tax (enter your projected 2026 income and deductions; the program will automatically calculate the new quarterly voucher amounts).

Option 3...

1. Open or continue your return.
2. Click on Forms Mode, and Click Open Form and type "What-If" (you can create a side-by-side scenario (Column 1 is your current 2025 return; Column 2 can be your projected 2026 return).
3. After you fill out Column 2 with your higher income, you can go back to your state's estimated tax worksheet and tell it to use the "What-If" data to generate the vouchers.

Note: Even if your income is skyrocketing, most states (like the IRS) only require you to pay 100% or 110% of your 2025 tax to avoid underpayment penalties ("Safe Harbor").  However, paying based on your 2026 projection may prevent you having to owe a massive lump sum later.

[amt_blues]

Thank you!

The Estimated Tax Worksheet at Option 2 has already been filled in with the increased income. Perhaps based on the Federal estimated tax.

Another question. The state estimated tax is spread out in four quarterly payments, which I'm familiar with. The Federal estimated tax is lumped in one payment for the last quarter, which I'm not familiar with. Why the difference?

[Mike9241]

Even though your federal taxes will increase for 2026, the IRS provides a safe harbor (no underpayment of estimated tax penalty)  that might allow you to pay less than what was calculated. The rule is timely estimated tax payments and withholding must be 100% of your 2025 taxes, 100% jumps to 110% if your 2025 AGI is $150,000 or more. States have their own rules. Turbotax. Turbotax can calculate your required estimated tax payments using the safe harbor rules. However, I realize some taxpayers do not like a big bill come  4/15/2027, while others prefer not ot make an interest-free loan to the tax authorities