Quarterly Tax Strategy California

Why Quarterly Tax Planning Matters

Most tax planning happens in December — too late to implement many strategies. KDA's quarterly tax planning approach reviews your tax situation every quarter, allowing us to identify opportunities and implement strategies throughout the year. This proactive approach typically saves clients significantly more than year-end planning alone, and avoids the underpayment penalties that result from insufficient estimated tax payments.

California Estimated Tax Deadlines

California has unusual estimated tax payment deadlines that differ from the federal deadlines:

Note: California front-loads its estimated tax payments — 70% of the annual estimate is due by June 15. Missing the California Q2 deadline is a common and costly mistake.

Safe Harbor Rules

You can avoid underpayment penalties by meeting one of the safe harbor rules: (1) 100% of prior year tax — pay at least 100% of your prior year federal tax liability (110% if prior year AGI exceeded $150,000). California requires 100% of prior year California tax. (2) 90% of current year tax — pay at least 90% of your current year federal tax liability (66.67% for California). KDA calculates the safe harbor amount for every client at the beginning of each year and adjusts estimated payments as income changes.

Q1 Strategy (January–March)

Q1 actions: (1) File prior year returns or extensions by April 15. (2) Make IRA and HSA contributions for the prior year (deadline: April 15). (3) Establish the estimated tax payment schedule for the current year. (4) Review retirement plan contributions — if you have a SEP-IRA, the contribution deadline is the extended return due date (October 15). (5) Evaluate whether a new retirement plan should be established for the current year. (6) Review the PTET election status for pass-through entity owners.

Q2 Strategy (April–June)

Q2 actions: (1) Make the Q1 federal and California estimated tax payments by April 15. (2) Make the Q2 California estimated tax payment by June 15 — remember, California requires 40% of the annual estimate by this date. (3) Review year-to-date income and adjust estimated payments if income is significantly higher or lower than expected. (4) Review capital gains and losses — consider tax-loss harvesting if you have significant unrealized losses. (5) Review retirement plan contributions and adjust if needed.

Q3 Strategy (July–September)

Q3 actions: (1) Make the Q3 federal estimated tax payment by September 15 (no California Q3 payment required). (2) Review year-to-date income and project full-year tax liability. (3) Begin year-end tax planning — identify strategies to implement before December 31. (4) Consider accelerating deductible expenses into the current year if you expect to be in a higher bracket. (5) Review business entity structure — if restructuring is needed, begin the process now to be effective January 1.

Q4 Strategy (October–December)

Q4 actions: (1) Implement year-end tax strategies before December 31. (2) Make charitable contributions — consider a donor-advised fund for appreciated assets. (3) Maximize retirement plan contributions. (4) Harvest capital losses to offset gains. (5) Review and pay the PTET for pass-through entity owners. (6) Make the Q4 federal and California estimated tax payments by January 15. (7) Gather tax documents for the upcoming filing season. KDA schedules Q4 planning meetings with all clients in October or November.