St. Louis County Property Tax: Rates & Appeals (2026)

Direct answer: St. Louis County’s 2026 residential assessment appeal deadline was Monday, July 13, 2026—the second Monday in July. File with the St. Louis County Board of Equalization (BOE) online through the county BOE page, or by paper form postmarked/delivered to Board of Equalization, 41 S. Central Ave., Clayton, MO 63105; as of July 30, 2026, the next regular annual deadline is expected to be Monday, July 12, 2027, unless the BOE extends it. (fy.stlouiscountymo.gov)

How assessments work in St. Louis County

St. Louis County is in Missouri’s odd-year reassessment system. Real estate is reassessed every two years in odd-numbered years; 2025 was the last general reassessment year, 2026 is an off-year unless the property had a significant physical change, and 2027 is the next general reassessment. The Assessor’s office says Change of Assessment Notices go to residential owners in May of reassessment years, while some owners can receive a notice in an even year for changes like new construction or demolition. (ms.stlouiscountymo.gov)

For a home, the key number is fair market value as of January 1 of the reassessment year. Missouri then applies the residential assessment factor: 19% of market value becomes assessed value. St. Louis County’s own budget example uses the same calculation: appraised value × 19% = assessed value, then tax rate per $100 of assessed value. (so.stlouiscountymo.gov)

St. Louis County’s Real Property Division values roughly 400,000 residential and commercial parcels. Local procedures matter: the county says appraisers physically inspect every residential property whose value rises by more than 15% from the prior reassessment, every parcel at least once every six years, and any property when the owner requests a reinspection. (so.stlouiscountymo.gov)

Your tax bill is not just “the county rate.” The county collects for schools, municipalities, service districts, fire districts and others. But the county’s own 2025 residential real estate levy remained $0.379 per $100 of assessed valuation, and the county portion represented about 4.7% of the average taxpayer’s property-tax bill. (st.stlouiscountymo.gov)

Whether you should appeal

Appeal if you can prove one of three things St. Louis County recognizes on its BOE form: property value, classification, or ratio. Value is the most common homeowner argument: comparable sales, a recent arm’s-length purchase, an independent appraisal, or condition evidence showing the county’s market value is too high. Classification is for cases where the property type is wrong. Ratio is a harder argument: you are saying your property was assessed at a higher percentage of market value than other properties in the same class. (co.stlouiscountymo.gov)

Do not appeal just because the tax bill feels high. The BOE is reviewing the Assessor’s value or classification, not school district levies or city tax rates. A strong appeal usually starts with the county’s parcel record: living area, basement finish, grade, condition, lot size, and recent sales used around your neighborhood. If the county has your home as 2,400 square feet but it is 2,100, or it lists a finished basement that is unfinished, that is appeal-worthy evidence.

A realistic savings example using the actual county levy: assume the Assessor values your home at $350,000, but you prove $320,000. The market-value reduction is $30,000. Residential assessed value falls by 19%, or $5,700. At the county residential levy of $0.379 per $100, the county portion of the savings is about $21.60 per year: $5,700 ÷ 100 × $0.379. Your total savings on the full bill will be larger if your school, fire, city and other district rates also apply to the lower assessed value; use the composite rate printed on your own tax bill for that estimate. (st.stlouiscountymo.gov)

I did not find an official St. Louis County publication giving homeowner appeal success rates, median reductions, or win rates. Treat any non-official “average reduction” claims cautiously.

Step-by-step how to file

1. Get the right form. For a residential real-estate appeal, use the 2026 Property Assessment Appeal Form. St. Louis County also lists BOE supplemental forms, including BOE Representative Authorization Form, Appeal Hearing Attendance Waiver, and personal-property supplemental forms. A separate appeal form is required for each locator/account number. (jw.stlouiscountymo.gov)

2. Know the deadline rule. Missouri law generally requires county BOE assessment appeals before the second Monday in July; St. Louis County’s 2026 online filing page gave the concrete date as July 13, 2026. Paper appeals had to be postmarked or delivered by that date, and supporting documents also had to be filed by that date to be considered. (revisor.mo.gov)

3. Choose a filing method. Online filing is the county’s preferred method and is routed through the BOE page; the county says online filing produces faster processing. Paper filing is allowed by mail or delivery/drop box at Board of Equalization, 41 S. Central Ave., Clayton, MO 63105. If evidence is not uploaded with the online appeal, St. Louis County says it may be submitted by email, mail, or in person/drop-off by the same deadline; the BOE email shown in county materials is boe@stlouiscountymo.gov. (co.stlouiscountymo.gov)

4. Put a number on it. The form asks for the owner’s opinion of fair market value. Do not write “too high.” Write the value you can support—for example, “$320,000 as of Jan. 1, 2025”—and attach the evidence.

5. Attach proof. St. Louis County specifically lists appraisal reports, construction/repair estimates, photos, sales contracts, and a written supporting statement as useful evidence. File it with the appeal if possible; late evidence may not be considered. (co.stlouiscountymo.gov)

Fee: I found no St. Louis County BOE filing fee in the official appeal instructions or form. If you hire an appraiser or representative, that is your cost.

What happens after

The appeal authority is the St. Louis County Board of Equalization. St. Louis County’s budget describes the Boards of Equalization as independent bodies whose members are appointed by the County Executive, approved by the County Council, and report to the Director of Revenue. A second Board was created in 2021, and the county’s 2025 budget funded a third Board and more hearing-officer days because more appeals were anticipated. (so.stlouiscountymo.gov)

For 2026, the county form says hearings are conducted by video or telephone conference only. You can also choose the non-oral option: waive appearance, submit documents and written statements, and receive a decision without the Board treating non-attendance against you. Hearing notices are emailed or mailed to the owner’s address of record or representative/alternate address. (jw.stlouiscountymo.gov)

Decision timing is partly controlled by state law. In a Missouri charter county, the county BOE must complete its business by the fourth Saturday in August; in 2026, that was August 22, 2026. If you lose or only receive a partial reduction, the next step is usually the Missouri State Tax Commission. The STC says a Complaint for Review of Assessment is due by September 30 of the assessment year or within 30 days of the BOE decision, whichever is later, and you normally must upload the BOE decision letter. (revisor.mo.gov)

Local tips

First, make the Assessor’s record work for you. Because St. Louis County physically reinspects properties with large reassessment increases and says owners may request reinspection, condition evidence is especially useful: roof age, foundation issues, water damage, dated kitchens, bids for major repairs, and photos.

Second, compare sales by school district and municipality, not just ZIP code. St. Louis County tax bills and market values vary sharply because the bill includes school, municipal, fire, service-district and other levies; a Ballwin comp may not help a Lemay house if buyers price those markets differently. (st.stlouiscountymo.gov)

Third, check relief programs even if you do not appeal. Missouri’s Property Tax Credit / Circuit Breaker can help qualifying seniors and 100% disabled individuals; for 2025 claims, the Department of Revenue lists a maximum credit of $1,100 for owners and $750 for renters, with income limits. St. Louis County also operates a Senior Property Tax Freeze program; local county materials direct residents to the Senior Property Tax Freeze application and email, and 2026 public notices reported a June 30 application/renewal deadline that was later extended to July 10. Always verify the current year’s freeze window before relying on it. (dor.mo.gov)

Finally, remember payment timing is separate from appeal timing. St. Louis County taxes are generally billed in the fall and due by December 31; unpaid taxes become delinquent after that, with penalties and interest. Appealing value does not automatically excuse missing the tax-payment deadline. (so.stlouiscountymo.gov)

St. Louis County Property Tax Rate

City of St. Louis, Missouri latest published residential real property tax rate is 8.1867 per $100 of assessed value for 2025; residential real property is assessed at 19% of market value. The 2026 tax rate was not yet set in the official sources reviewed. The City’s 2025 calculation guide gives a $200,000 residential market value example: assessed value $38,000 and estimated tax $3,110.95 using ($38,000 ÷ 100) × 8.1867.

Source: https://www.stlouis-mo.gov/government/departments/assessor/real-estate/upload/how-to-calculate-taxes-2025-divide-100.pdf

When Are Property Taxes Due in St. Louis County?

Real estate taxes are due by December 31 of each year. The Collector offers a pre-pay program for future personal property or real estate tax liabilities; there is not a set payment plan or schedule, payments may be made as often or seldom as desired, and payments must be made by September 30 to be applied to the current calendar year.

This is not the same as the assessment appeal deadline above. The appeal deadline is your window to contest your assessed value; the payment due date is when the resulting tax bill must be paid. Missing one does not affect the other, but missing either has real consequences — one forfeits your right to appeal for the year, the other can trigger penalties and interest.

Source: https://www.stlouis-mo.gov/government/departments/collector/real-estate-tax/index.cfm

Property Tax Exemptions in St. Louis County

• Senior Citizen Property Tax Freeze Credit — City of St. Louis senior homeowners who are age 62 or older as of December 31 of the current year, own or have a legal/equitable interest in their primary residence in the City, are liable for its taxes, occupy it as their primary dwelling for most of the year, have prior-year property taxes paid, and meet the property value limit; tax-abated properties are not eligible while abated.. Freezes the City’s property taxes/limits future increases for eligible residential real estate; it does not freeze other taxes such as public schools, public library, museum and zoo district, etc., and does not apply to vehicles or other personal property. Yes, apply or renew annually through the City of St. Louis Assessor’s Office. Apply by Standard annual application window: March 1–June 30.. (Source: https://www.stlouis-mo.gov/government/departments/assessor/real-estate/senior-tax-freeze/index.cfm)
• Missouri Property Tax Credit (Circuit Breaker) — Certain Missouri senior citizens and 100% disabled individuals; the official qualification chart includes owners who owned and occupied the home all year with income limits, and categories for age 65+ Missouri residents, 100% disabled veterans, 100% disabled individuals, and certain surviving spouses age 60+ receiving surviving-spouse Social Security benefits.. Maximum credit is $1,100 for owners who owned and occupied their home; actual credit depends on real estate taxes paid and total household income. Yes, file a Missouri Property Tax Credit claim; filing options include e-file, Form MO-PTC for claim-only filers, or MO-1040 with MO-PTS when applicable. (Source: https://dor.mo.gov/taxation/individual/tax-types/property-tax-credit/)
• Disabled Prisoner of War Real Property Tax Exemption — Former prisoner of war who is also a veteran of the U.S. or Missouri armed forces, became 100% disabled as a result of military service, and owns and occupies the home as a primary residence.. Exemption from real estate taxes; applies only to real property, not personal property, and does not extend to surviving spouses or to 100% disabled veterans who were not POWs. Yes, initial application/document submission; once approved, it applies as long as the owner owns and occupies the property and there is no need to apply again. (Source: https://www.stlouis-mo.gov/government/departments/assessor/real-estate/obtain-pow-exemption.cfm)
• Residential Natural Disaster / Tornado-Damaged Property Tax Relief — City of St. Louis residential property owners whose property was made unoccupied and uninhabitable by a natural disaster; the City page specifically addresses properties affected by the May 16, 2025 tornado.. If approved, the assessed value is adjusted to a prorated amount and taxes are figured on the prorated assessed value; the amount varies depending on how long the property is uninhabitable/unoccupied. Yes, apply online or by mail/email with property address, owner contact information, damage description, dates unoccupied/reoccupied, and repair-cost documentation when possible. (Source: https://www.stlouis-mo.gov/government/departments/assessor/real-estate/disaster-tax-relief/property-tax-relief-service.cfm)

How to Look Up Your Property Record in St. Louis County

You can look up your property's official record at https://www.stlouis-mo.gov/data/address-search/index.cfm. The City of St. Louis Address & Property Search lets users search by address or parcel and shows real estate/property information including taxes, valuation, assessment, sales information, land use, ownership/basic information, zoning, maps/geography, and real estate tax history.