St. Charles County: CPA, tax and bookkeeping services by community

Services and starting prices.

• 01

  Monthly Accounting

  From $400/mo

  Transaction categorization, account reconciliations, financial statements and regular accounting support.

• 02

  Tax Preparation

  From $300

  Individual returns (federal and one state) from $300; business returns from $750.

• 03

  Accounting + Tax + Planning

  From $900/mo

  Monthly accounting and reporting, business and owner tax returns, proactive tax planning and year-round CPA access.

  Founding Client Rate: $825/month for your first 12 months when you engage by March 31, 2027. Terms

• 04

  Law Firm Accounting

  From $900/mo

  For solo attorneys and small law firms: monthly accounting, financial reporting, business and owner returns, tax planning and CPA consultation.

Starting prices. Your scope and price are agreed in writing before work begins.

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St. Charles County at a glance

• Part of St. Louis, MO-IL

  metropolitan statistical area

  Source: U.S. Census Bureau, Vintage 2024 metropolitan and micropolitan statistical area population estimates (OMB July 2023 delineation)

• Borders Illinois

  Calhoun County, Jersey County, Madison County

  Source: U.S. Census Bureau, County Adjacency File 2023

• About 1%

  of workers who live in St. Charles County work outside Missouri

  Source: U.S. Census Bureau, American Community Survey 2023 5-year estimates, table B08007 (place of work: state and county)

Businesses and work in St. Charles County

• 8,946

  business establishments with paid employees in St. Charles County

  Source: Census County Business Patterns 2023

• 126

  law offices with paid employees in St. Charles County

  Source: Census County Business Patterns 2023

• 195

  physician offices with paid employees in St. Charles County

  Source: Census County Business Patterns 2023

• 431

  real estate firms with paid employees in St. Charles County

  Source: Census County Business Patterns 2023

• 738

  restaurants with paid employees in St. Charles County

  Source: Census County Business Patterns 2023

Tax offices in St. Charles County

• St. Charles County Assessor

  County property assessment.

  201 N. Second St., St. Charles, MO 63301

  Phone 636-949-7425

  Official website

• St. Charles County Collector of Revenue

  County property tax collection.

  201 N. Second St., Suite 134, St. Charles, MO 63301

  Phone 636-949-7470

  Official website

• Missouri Department of Revenue, Taxation Division (business tax)

  State tax and revenue agency.

  301 West High St., Room 102, Jefferson City, MO 65101

  Phone 573-751-5860

  Official website

• IRS Taxpayer Assistance Center - Chesterfield

  Federal tax help in person.

  1122 Town and Country Commons, Chesterfield, MO 63017

  Phone (636) 255-1599

  Official website

Source: each office's official website, checked October 16, 2026.

Communities in St. Charles County

• No community in St. Charles County has a page of its own; this page serves the whole county.
• Other communities in St. Charles County, served from this page: Lake St. Louis (city), Dardenne Prairie (city), O'Fallon (city), St. Charles (city), St. Peters (city), Wentzville (city).

Sources

• U.S. Census Bureau, Vintage 2024 metropolitan and micropolitan statistical area population estimates (OMB July 2023 delineation) (July 1, 2024 estimates; delineation of July 2023; official statistics)
• U.S. Census Bureau, County Adjacency File 2023 (2023; official statistics)
• U.S. Census Bureau, American Community Survey 2023 5-year estimates, table B08007 (place of work: state and county) (2019-2023 5-year estimates; official statistics)
• U.S. Census Bureau, ACS 2023 5-year places and county subdivisions with their counties (2019-2023 5-year estimates; official statistics)
• U.S. Census Bureau, County Business Patterns 2023, county file (establishments with paid employees by industry) (2023; official statistics)