Building without a permit in Missouri

What Missouri law says

Missouri has no statewide residential building code and no state crime of building without a permit, so both the permit requirement and its penalty come from city or county ordinance. Where a municipality enforces under its zoning enabling act, RSMo 89.120.2 makes it a misdemeanor to erect, construct, reconstruct, alter or convert a building in violation, punishable by not less than $10 and not more than $250 for each and every day the violation continues, or imprisonment for 10 days for each day it continues, or both, rising to $100 to $500 per day for a second or subsequent offense at the same building; in a city with more than 300,000 inhabitants the range is $10 to $500 per day and $250 to $1,000 per day for repeat offenses. In a first or second classification county that has adopted a building code, RSMo 64.200 makes any violation of the code a misdemeanor, and because no penalty is specified, RSMo 557.021.1 makes it a class A misdemeanor: up to one year in jail under RSMo 558.011.1(6) and a fine up to $2,000 under RSMo 558.002.1(2). Those local penalties are then capped by RSMo 479.353, which bars a court from assessing a fine plus court costs above $200 for a first municipal ordinance violation, $275 for a second, $350 for a third, and $450 for a fourth or later violation within a twelve month period, and bars confinement except for violations involving alcohol or controlled substances, violations endangering the health or welfare of others, or eluding or giving false information to a law enforcement officer. That cap reaches building enforcement because RSMo 479.350(4) defines municipal ordinance violation by listing the penalty statutes it covers, and both 89.120 and 64.200 are on the list. A city enforcing a building code under its general ordinance power instead runs against the older class ceilings: $500 and three months for third class cities (RSMo 77.590), $500 and 90 days for fourth class cities (RSMo 79.470), and $1,000 and twelve months for Kansas City (RSMo 82.300.1).

Cited from RSMo 479.353.1(1)(b) and 479.353.1(2); RSMo 479.350(4); RSMo 89.120.2; RSMo 64.200; RSMo 557.021.1; RSMo 558.011.1(6); RSMo 558.002.1(2); RSMo 77.590; RSMo 79.470; RSMo 82.300.1: official text. Localities enforce these rules and may add their own fees and procedures on top.

Can you get a permit after the work is done?

No Missouri statute creates an as-built permit, a retroactive permit, an investigation fee, or a fee multiplier for construction already finished without a permit. That is left entirely to the local jurisdiction that issues permits, and the state supplies only the abatement machinery. RSMo 89.120.1 lets local authorities bring an action to prevent an unlawful erection, construction, reconstruction, alteration or conversion, to restrain, correct or abate the violation, and to prevent occupancy of the building, and RSMo 89.120.3 adds a $250 civil penalty when an owner served with an order to remove a violation fails to comply within 10 days. Under RSMo 67.400 and RSMo 67.410 any city, town, village or first classification county may, after notice and a hearing, order a building vacated, repaired or demolished, and the cost of that work is certified as a special tax bill that is a personal debt against the owner and a lien on the property until paid, payable in installments over as long as ten years. Fines under a dangerous building ordinance are capped at $1,000, or $2,000 where the owner does not live at the property (RSMo 67.410.4). The one after the fact permit path written into Missouri statute is narrow and applies only to septic work: RSMo 701.052.7 allows an emergency major modification or major repair of an on-site sewage disposal system without a permit, provided the city, county or department is notified by the fifth working day and provides an expedited review.

Cited from RSMo 89.120.1 and 89.120.3; RSMo 67.400; RSMo 67.410.1(4), 67.410.1(5), 67.410.4; RSMo 701.052.7: official text.

The typical path, whatever your locality calls it: stop any ongoing work, contact the permit office before they contact you, apply for the permit describing what was actually built, and expect the office to require opening up or inspecting concealed work. Voluntarily coming forward generally goes better than waiting for a complaint or a sale to surface it.

What Missouri permit offices charge when work starts first

The statute above sets the ceiling; the bill comes from the local office. 2 Missouri jurisdictions we cover publish a specific surcharge for work started before the permit, quoted here from the fee schedule or permit page we verified, each linked to the page that carries the citation.

• A reinspection is $75.00 under Sec. 18-20(h)(6), and building without the permit first triples the permit fee under Sec. 18-20(e)(2).

  Kansas City · from the deck permit page · last checked 16 Aug 2026

• Starting work before the permit issues triggers a surcharge that scales with the permit fee, from $35.00 on a $0 to $50.00 permit up to $1,005.00 over $10,000.00.

  St. Louis · from the plumbing permit page · last checked 16 Aug 2026

Jurisdictions not listed either publish no surcharge clause or publish one we could not quote from an official schedule; their permit pages state what we could verify.

Who can pull the permit

Missouri does not license general contractors at the state level and has no statewide owner-builder permit statute, disclosure affidavit, or resale restriction comparable to Florida's one year rule. Whether a homeowner may pull the permit and do the work is decided by the city or county that issues the permit. Where state law does speak, it is permissive: RSMo 327.101.2(5)(a) and RSMo 327.191.2(5)(a) let an unlicensed person render architectural and engineering services for the construction, remodeling or repair of a privately owned dwelling house, provided the drawings say the person is not licensed, so plans for a house do not have to be sealed by an architect or engineer. RSMo 701.055.1 expressly preserves a property owner's right to install, modify or repair their own on-site sewage disposal system as long as the state standard is met, and RSMo 701.055.2 adds that no permit or contractor registration is required simply to clean it. RSMo 700.656.5 exempts a person who installs a manufactured home on his or her own property for his or her own occupancy from the otherwise mandatory state installer license. None of these exemptions excuses a local permit where the local jurisdiction requires one.

Cited from RSMo 701.055.1 and 701.055.2; RSMo 327.101.2(5)(a); RSMo 327.191.2(5)(a); RSMo 700.656.5: official text.

Selling or buying in Missouri?

• Selling a house with unpermitted work
• Buying a house with unpermitted work

How Missouri compares: building without a permit, state by state.

Your local permit office

Enforcement, after-the-fact fees, and the exact fix-it process are local. We cover these Missouri permit offices:

• Kansas City
• St. Louis

Official sources

• https://revisor.mo.gov/main/OneSection.aspx?section=479.353
• https://revisor.mo.gov/main/OneSection.aspx?section=89.120
• https://revisor.mo.gov/main/OneSection.aspx?section=701.055