This tool is intended to help you determine how much California income tax you would owe given the data you provide. The California income tax is based on the federal adjusted gross income (AGI), and then, additions and subtractions are made to account for differences in the federal and state tax laws. This means you need to provide and accurate estimate of the federal AGI and some of the values that were used to calculate it.
The blue fields are computed from the information you provide. The green fields are where you enter information. The first column shows where the information can be found in the tax return. Click this link for more help with this tool.
The tax formula below describes, at a high level, how the tax is calculated. The value of each item in the tax formula is shown in the Estimated Tax Calculation. You can see a brief description of any of the items by moving the mouse over the calculated value in the Estimated Tax Calculation.
540, line 17, State AGI
= Federal AGI - Subtractions + Additions
540, line 19, Taxable Income
= State AGI - Deductions
540, line 31, Income Tax
= Tax on Taxable Income
540, line 35, Total Tax
= Income Tax - Exemptions - Non-refundable Credits + Other Taxes
540, line 111, Refund / Amount Due
= Total Tax - Payments - Refundable Credits
Taxpayer's Name
Version
Filing Status
Today's Date
0
Taxpayer's Birthday
Taxpayer's Age
0
Spouse's Birthday
Spouse's Age
0
540, line 11
Exemptions
0
540, line 14
Subtractions
0
540, line 16
Additions
0
540, line 18
Deductions
0
540, line 48
Non-refundable Credits
0
540, line 74-77
Refundable Credits
0
540, line 64
Other Taxes
0
540, line 78
Payments
0
540, line 17
State AGI
0
540, line 19
Taxable Income
0
540, line 31
Income Tax
0
540, line 35
Total Tax
0
540, line 111-115
Refund (-) / Amount Due (+)
0
540-ES
Estimated Payment April (30%)
0
540-ES
Estimated Payment June (40%)
0
540-ES
Estimated Payment September (0%)
0
540-ES
Estimated Payment January (30%)
0
540, line 13
Federal AGI
540, line 10
Number of Dependents
CA 540, part IA, line 2
Interest on U. S. Treasury Obligations
CA 540, part IA, line 5
Military Retirement Income
CA 540, part IA, line 6b
Taxable Social Security
CA 540, part IB, line 1
State Tax Refund
CA 540, part IB, line 7
Unemployment Income
CA 540, part IB, line 8b
California Lottery Winnings
CA 540, part IB, line 8f
Non-qualified HSA Distributions
CA 540, part IC, line 19
Alimony Paid
CA 540, part IC, line 24
Other Subtractions
CA 540, part IA, line 1h
HSA Employer Contributions
CA 540, part IB, line 2
Alimony Received
CA 540, part IB, line 8c
Home Loan Debt Cancellation
CA 540, part IB, line 8c
Employer Paid Student Loan Payments
CA 540, part IC, line 11
Educator Expenses
CA 540, part IC, line 13
HSA Contributions
CA 540, part IC, line 20
IRA Contributions
CA 540, part IC, line 24
Other Additions
CA 540, part II, line 17
Federal Itemized Deductions
CA 540, part II, line 5a
State Income Tax or Sales Tax
CA 540, part II, line 4
Qualified HSA Distributions
CA 540, part II, line 5e
SALT Limit Excess
CA 540, part II, line 8a
Home Mortgage Interest Limit
CA 540, part II, line 20
Tax Preparation Fee
CA 540, part II, line 21
Safe Deposit Box
CA 540, part II, line 21
Investment Fee
CA 540, part II, line 16
Other Deductions
540, line 92
Shared Responsibility Penalty
540, line 112
Interest and Penalties
540, line 113
Underpayment of Estimated Tax
540, line 91
Use Tax
540, line 63
Other Taxes
540, line 40
Child and Dependent Care Credit
540, line 46
Renter's Credit
540, line 45
Other Non-refundable Credits
540, line 75
Earned Income Tax Credit (EITC)
540, line 76
Young Child Tax Credit
540, line 77
Foster Youth Tax Credit
540, line 78
Other Refundable Credits
540, line 71
Withholding
540, line 72
Estimated Payments
540, line 78
Other Payments
540, line 110
Contributions