What We're Trying to Accomplish
The IRS doesn't require perfection, it requires adequacy. There are two separate standards for what counts as "adequate," and satisfying either one fully protects you from underpayment penalties, regardless of how much you ultimately owe at filing time. Our job is to identify which method fits your situation, calculate your required payments, and make sure those payments land in the right quarters.
Method One
Prior Year Safe Harbor
Based on last year's actual tax liability: our preferred starting point
The prior year safe harbor is the simplest and most reliable method for most clients. The calculation uses your completed prior year return as the baseline; no projections, no estimates, no uncertainty about what this year's income will be.
1 Pull your total tax from your most recently filed return (Line 24 on Form 1040)
2 If your prior year AGI was $150,000 or less, your safe harbor target is 100% of that number
3 If your prior year AGI exceeded $150,000 (or $75,000 filing separately), your safe harbor target is 110% of that number
4 Divide the target by four and pay that amount by each quarterly due date
One important step: Before dividing by four, subtract any tax withholding you already expect to have for the year; from a W-2 job, pension, Social Security, or backup withholding on investment accounts. Your safe harbor target represents your total required tax coverage and withholding counts toward that total. Only the remaining balance after withholding needs to be covered through estimated payments. Skipping this step leads to overpaying quarterly, sometimes significantly.
Method Two
90% of Current Year Projected Tax
Based on real-time income data, used when it produces a lower payment
The 90% current year method calculates your estimated tax based on what we project your income to be this year. It requires more active management including income projections, updated deduction estimates, and sometimes mid-year recalculations, but it can produce meaningfully lower quarterly payments when income is down from the prior year, or when significant deductions are anticipated.
1 Estimate total gross income from all sources for the current year
2 Subtract anticipated deductions: business expenses, retirement contributions, self-employment tax deduction, QBI deduction, and others
3 Apply current year tax brackets and rates to the resulting taxable income to project total federal tax
4 Multiply projected total tax by 90%. This is your current year safe harbor target
5 Subtract any withholding already expected to determine the net estimated payment obligation
6 Divide by four or weight payments to match quarterly income if income is uneven
Choosing Between Them
Which Method Is Right for Your Situation?
✓ Prior Year Safe Harbor Works Best When...
Income is similar to or higher than last year
You prefer a fixed, predictable quarterly payment
Income is difficult to project mid-year
You want certainty without ongoing calculation
→ Current Year 90% Works Best When...
Income dropped significantly from last year
You have large new deductions (new retirement plan, business loss)
You want to minimize cash going out each quarter
Important: The two methods are not mutually exclusive over the course of a year. We may start with the prior year safe harbor in Q1 when current year data is limited, then shift to the 90% method in Q3 once we have a clearer picture of actual income.The goal is always the lowest defensible payment, not the highest.
What We Need to Calculate Your Payments
✔ Your most recently filed federal return (for the prior year safe harbor baseline)
✔ YTD revenue and expense summary for any business income (updated each quarter)
✔ Expected W-2 income and withholding for the year
✔ Anticipated investment income, capital gains, or large one-time transactions
✔ Any new retirement plan contributions, major deductions, or entity changes
✔ Prior year state tax return (for state estimated payment calculations)
The estimated payment calculation is one of the most direct forms of tax planning available; it's where we prevent problems rather than respond to them. If you have questions about your current payment schedule or want to review whether you're using the right method this year, reach out any time.
Colorado Wealth Group ("CWG") is a financialservices group offering investment advisory services through Savvy Advisors,Inc. ("Savvy"). Savvy is an investment advisor registered with theSecurities and Exchange Commission ("SEC"). CWG is not a separatelyregistered investment advisor.
Material prepared herein has been created forinformational purposes only and should not be considered investment advice or arecommendation. Information was obtained from sources believed to be reliablebut was not verified for accuracy. It is important to note that federal taxlaws under the Internal Revenue Code (IRC) of the United States are subject tochange, therefore it is the responsibility of taxpayers to verify theirtaxation obligations.
