Estimated tax planner

Working out what to pay

1. Start with last year’s return, the first section below. You need four numbers: total tax and AGI from Form 1040 (lines 24 and 11), and the same two from your California Form 540. Paying what you paid last year is enough to avoid a penalty, whatever this year turns out to be.
2. Then this year — Income and Deductions. Your best guess is fine; come back and change it whenever the picture moves.
3. Then pay the schedule. Switch to Quarterly for the four dates. The two agencies split the year differently, and anything already withheld is taken off for you.