St. Louis Income Tax Calculator: Rates, Credits, and Filing

To estimate what you owe with a St. Louis income tax calculator, multiply your taxable earnings by 0.01. The city levies a flat 1% earnings tax, so $55,000 in qualifying wages produces a $550 annual liability, and $80,000 produces $800. Most W-2 employees have the full amount withheld paycheck by paycheck, but self-employed workers, non-residents who split time between locations, and anyone whose withholding came up short need to run the numbers and settle up by April 15.¹

Do You Owe the Tax in the First Place

Two groups owe the 1%: anyone who lives in the City of St. Louis regardless of where their employer sits, and anyone who performs work inside city limits regardless of where they live.¹ Physical presence drives the rule for non-residents. The tax follows where you actually do the work, not where the company is headquartered, which is why remote and hybrid workers so often end up over-withheld.

Passive income is outside the tax. Social Security, pension distributions, interest, dividends, capital gains, and rental income are not “earned” for this purpose, so a retiree living in St. Louis on pension and investment income likely owes nothing. The tax applies to wages, salaries, commissions, bonuses, and fees paid to independent contractors, including anything reported on a 1099-NEC for freelance work performed in the city.

What Number to Multiply by 1%

Your starting figure depends on how you earn:

If you’re a W-2 employee, use Box 18 (local wages) as the earnings figure and compare the result to Box 19 (local tax withheld) to see whether you still owe or are due a refund.
If you’re self-employed or freelance, use your net profit from work performed in St. Louis, drawn from your 1099-NEC forms and profit-and-loss statement.
If you’re a non-resident seeking a refund for days worked elsewhere, you’ll need your employer to certify the whole days you worked outside city limits. Vacation, sick days, and holidays don’t count as days worked outside the city.²

The Straight 1% Calculation

Multiply taxable earnings by 0.01. Someone earning $65,000 in qualifying wages owes $650. If Box 19 shows $650 withheld, you’re square. If only $500 was withheld, you owe $150 at filing. If $700 was withheld, you can claim a $50 refund.

The Non-Resident Refund Formula

This is where non-residents most often leave money on the table. If your employer withheld the full 1% as though you worked in the city every day, you can reclaim the share tied to days you physically worked elsewhere. The city uses a standard 260-day work year:²

Start with total work days (standard is 260).
Count whole days worked outside St. Louis. A day only counts if you neither started nor finished your workday in the city.
Divide step 2 by step 1 to get your out-of-city percentage.
Multiply gross wages by that percentage. That’s your non-residency deduction.
Subtract the deduction from gross wages, multiply the result by 0.01, and compare to what was withheld.

Worked example. A non-resident earning $80,000 who spent 100 days working outside the city: 100 ÷ 260 = 38.46%. The non-residency deduction is $80,000 × 0.3846 = $30,768. Taxable city earnings drop to $49,232, so the actual tax is $492.32. If the employer withheld the full $800, the refund is about $308.

Credit If You Already Paid Another City

St. Louis residents who pay an earnings or income tax to another city or political subdivision can claim a credit so the same income isn’t taxed twice. The credit is claimed on Form E-1CR as a supplement to the regular E-1 return and cannot exceed what St. Louis would otherwise charge on that income.³

Filing and Paying What the Calculator Shows

Individuals reconcile withholding on Form E-1.¹ Non-residents claiming a refund for days worked outside the city file Form E-1R instead, with employer verification of the days claimed.⁴ Residents claiming the other-city credit attach Form E-1CR.

The return itself cannot be filed electronically; it must be mailed, faxed, or emailed to the Collector of Revenue. Payment, however, can be made online through the city’s payment portal.⁵

One detail catches people off guard: individual filers cannot request a filing extension.⁶ There is no extra time, even if you have a federal extension. The April 15 deadline is firm.

What a Late Payment Adds to the Number

Missing the deadline is expensive. The penalty is 5% of the unpaid tax for each month or partial month the return is late, capping at 25%. Interest accrues on top of that at 1% per month (12% annually) until the balance is paid in full.⁷ On a $500 bill, five months of inaction adds $125 in penalties and $25 in interest, taking the total to $650.

Because individuals have no extension option, pay what you can by April 15 even if the paperwork isn’t finished. Shrinking the unpaid balance shrinks the base that penalties and interest run against. Keep copies of every filing and payment confirmation in case the Collector follows up.

Businesses operating in St. Louis owe the same 1% on net profits using Form E-234, with different rules for extensions, account setup, and multi-location allocation. If you’re calculating for a business rather than yourself, the forms and formula differ from everything above.⁸

1
City of St. Louis. E-1 Form
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St. Louis Collector of Revenue. City of St. Louis Individual Earnings Tax Refund Request
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City of St. Louis. Earnings Tax Forms and Documents
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City of St. Louis. E-1R Form
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City of St. Louis. File Individual Earnings Taxes
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City of St. Louis. E-8 Form
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City of St. Louis. Individual Earnings Tax Information
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City of St. Louis. Business Earnings Tax Information