Nonpartisan · Data from OpenStates / Plural Policy · Missouri
Republican
· State Representative
Mike Costlow
Represents District 108 in the House of Representatives.
Votes with Republicans
99%
on 129 party-line votes · House Republicans median 96%
Cast a vote
92%
Yea or Nay on 371 of 404 roll calls · House median 93%
Their bills that became law
0 of 34
as a primary sponsor, this session · Republicans median 0
Roll calls on record
404
2026 Regular Session
Votes and bills updated Oct 11, 2026 from LegiScan (CC BY 4.0), which republishes the legislature’s own records. Profile details from OpenStates / Plural Policy. Figures cover 2026 Regular Session.
How Mike Costlow votes
A party-line vote is a roll call where most voting Democrats and most voting Republicans took opposite sides. Absences and not-voting are never counted. Same method as our Congress pages.
Where Mike Costlow sits in the House
Each dot is one member of the House, placed by how often they voted on the Democratic side of party-line votes. Mike Costlow is circled.
Always on the Republican sideAlways on the Democratic side
Times they broke with their party
1 of 129 party-line votes.
HB2167 · Modifies provisions for the staffing of the attorney general's office and the capitol
House: HBs FOR THIRD READING HB 2167, E.C. · 2026-03-02 · Passed 88–58 · most Republicans voted the other way
Closest votes they cast
Roll calls decided by the fewest votes, one per bill.
HB2426 · Establishes provisions relating to parental rights
House: HBs FOR THIRD READING HCS HB 2426 · 2026-04-30 · Passed 70–60
SB1002 · Creates and modifies provisions relating to elections submitted to the people by a school board of any school district located in St. Charles County
House: SBs 3rd READ – INFORMAL SS SB 1002 · 2026-05-15 · Passed 81–66
HB2002 · Appropriates money for the expenses, grants, refunds, and distributions of the State Board of Education and Department of Elementary and Secondary Education
House: BILLS IN CONFERENCE CCS SS SCS HCS HB 2002 · 2026-05-06 · Passed 83–68
HB2003 · Appropriates money for the expenses, grants, refunds, and distributions of the Department of Higher Education and Workforce Development
House: HABs FOR THIRD READING HCS HB 2003 · 2026-03-26 · Passed 83–66
HB2748 · Modifies requirements for physical education in schools
House: HBs 3rd READ – INFORMAL HCS HB 2748 · 2026-03-26 · Passed 82–65
Democrats they vote with most
Share of contested roll calls (the losing side got at least 10%) where both voted and landed on the same side. Unanimous votes are left out, because on those everyone agrees.
Marlene TerryDemocrat · District 66 · 184 shared contested votes
53%
Ian MackeyDemocrat · District 99 · 180 shared contested votes
41%
Will JobeDemocrat · District 21 · 177 shared contested votes
40%
Their session, month by month
Dark bars are roll calls they were recorded on each month; the red part is the ones without a Yea or Nay (33 in all). Gaps are months the chamber wasn’t voting.
← Missouri Delegation
YeaYeaYeaYeaYeaYeaYeaYeaYeaAbsentYeaYeaAbsentYeaYeaYeaYeaYeaNayYeaYeaYeaNayYeaYeaYeaYeaYeaYeaYeaYeaYeaYeaYeaYeaYeaYeaYeaYeaYeaAbsentYeaAbsentYeaYeaNayYeaYeaYeaYeaYeaNayYeaYeaNayNayYeaYeaYeaNay
Their bills, from filing to law
Bills Mike Costlow was a primary sponsor of this session. Most bills from either party never leave committee; in Illinois many never get past the Assignments or Rules committee.
Introduced34
Out of committee7
Passed one chamber2
Passed both chambers0
Became law0
Never left committee27
For comparison, the median Republican member of the House has 0 bills that became law this session.
Modifies Supreme Court Rule 33.01 relating to conditions of release from custody in criminal proceedings
Not out of committeeReferred: Emerging Issues(H) · 2026-05-15
Establishes provisions regulating the display of flags at public buildings
Not out of committeeReferred: Emerging Issues(H) · 2026-05-15
Creates the Manufacturing Opportunity Zones Act for large manufacturing developments with access to transportation and proximity to electricity, gas, and water
Not out of committeeReferred: Emerging Issues(H) · 2026-05-15
Allows election authorities to publish electronic voting records on the election authority's website
Not out of committeeReferred: Emerging Issues(H) · 2026-05-15
Provides that the court shall not order a parent to pay child support to the other parent for reasonable or necessary expenses of the child if the parents are awarded equal time with the child
Not out of committeeReferred: Emerging Issues(H) · 2026-05-15
Establishes the offense of impeding, threatening, or harassing a first responder
Not out of committeeReferred: Emerging Issues(H) · 2026-05-15
Enacts provisions governing United States founding documents displayed in public schools
Not out of committeeReferred: Emerging Issues(H) · 2026-05-15
Places restrictions on political subdivisions and homeowners' associations with respect to prohibitions against ownership or pasturing of non-nuisance domesticated animals for consumption
Not out of committeeReferred: Emerging Issues(H) · 2026-05-15
Modifies certain provisions relating to the renewable energy
Not out of committeeReferred: Emerging Issues(H) · 2026-05-15
Modifies provisions relating to additional protections to bear arms
Not out of committeeReferred: Emerging Issues(H) · 2026-05-15
Establishes programs for funding energy infrastructure projects.
Not out of committeeReferred: Emerging Issues(H) · 2026-05-15
Establishes the "Missouri Statewide Mechanical Contractors Licensing Act"
Not out of committeeReferred: Emerging Issues(H) · 2026-05-15
Modifies provisions governing income exempt from earnings tax
Not out of committeeReferred: Emerging Issues(H) · 2026-05-15
Modifies provisions relating to unlawful discriminatory practices
Not out of committeeReferred: Emerging Issues(H) · 2026-05-15
Modifies provisions relating to transportation network companies and establishes the offense of impersonating a transportation network company driver
Not out of committeeReferred: Emerging Issues(H) · 2026-05-15
Descriptions are the legislature’s own synopsis. Bill data from LegiScan, CC BY 4.0.
Loading committees…
SJR95 · 2026-05-15
Establishes the "Show-Me Prosperity Fund" (House: SJRs FOR THIRD READING SS SCS SJR 95)
SJR95 · 2026-05-15
Establishes the "Show-Me Prosperity Fund" (House: SJRs FOR THIRD READING SS SCS SJR 95)
SB1002 · 2026-05-15
Creates and modifies provisions relating to elections submitted to the people by a school board of any school district located in St. Charles County (House: SBs 3rd READ – INFORMAL SS SB 1002)
SB1002 · 2026-05-15
Creates and modifies provisions relating to elections submitted to the people by a school board of any school district located in St. Charles County (House: SBs 3rd READ – INFORMAL SS SB 1002)
SB1002 · 2026-05-15
Creates and modifies provisions relating to elections submitted to the people by a school board of any school district located in St. Charles County (House: SBs 3rd READ – INFORMAL SS SB 1002)
SB1002 · 2026-05-15
Creates and modifies provisions relating to elections submitted to the people by a school board of any school district located in St. Charles County (House: SBs 3rd READ – INFORMAL SS SB 1002)
SB1002 · 2026-05-15
Creates and modifies provisions relating to elections submitted to the people by a school board of any school district located in St. Charles County (House: SBs 3rd READ – INFORMAL SS SB 1002)
SB1135 · 2026-05-15
Creates "Bentley and Mason's Law" relating to child maintenance orders for certain persons convicted of the offense of driving while intoxicated (House: SBs 3rd READ – INFORMAL SS SB 1135)
SB1576 · 2026-05-15
Establishes the Missouri Ireland Trade Commission (House: SBs 3rd READ – INFORMAL SB 1576)
HB2636 · 2026-05-15
Establishes the "Uniform Mortgage Modification Act" (House: HBs WITH SENATE AMENDMENTS SS HB 2636, A.A.)
HB2636 · 2026-05-15
Establishes the "Uniform Mortgage Modification Act" (House: HBs WITH SENATE AMENDMENTS SS HB 2636, A.A.)
HB2896 · 2026-05-15
Modifies provisions relating to the governing bodies of certain public institutions of higher education (House: HBs WITH SENATE AMENDMENTS SS SCS HB 2896)
HB2896 · 2026-05-15
Modifies provisions relating to the governing bodies of certain public institutions of higher education (House: HBs WITH SENATE AMENDMENTS SS SCS HB 2896)
HB2896 · 2026-05-15
Modifies provisions relating to the governing bodies of certain public institutions of higher education (House: HBs WITH SENATE AMENDMENTS SS SCS HB 2896)
HB1696 · 2026-05-15
Modifies provisions relating to the right of sepulcher (House: HBs WITH SENATE AMENDMENTS SS SCS HCS HB 1696, A.A.)
HB1696 · 2026-05-15
Modifies provisions relating to the right of sepulcher (House: HBs WITH SENATE AMENDMENTS SS SCS HCS HB 1696, A.A.)
HB1696 · 2026-05-15
Modifies provisions relating to the right of sepulcher (House: HBs WITH SENATE AMENDMENTS SS SCS HCS HB 1696, A.A.)
SB1553 · 2026-05-15
Authorizes incentives for producing certain critical materials and pharmaceuticals (House: SBs 3rd READ – INFORMAL SS SB 1553)
SB1553 · 2026-05-15
Authorizes incentives for producing certain critical materials and pharmaceuticals (House: SBs 3rd READ – INFORMAL SS SB 1553)
SB890 · 2026-05-15
Repeals expired, terminated, sunset, and obsolete sections of law (House: SBs 3rd READ – INFORMAL SS SCS SB 890)
SB890 · 2026-05-15
Repeals expired, terminated, sunset, and obsolete sections of law (House: SBs 3rd READ – INFORMAL SS SCS SB 890)
SB913 · 2026-05-15
Modifies provisions relating to tax credits (House: SBs 3rd READ – INFORMAL SS SB 913)
SB913 · 2026-05-15
Modifies provisions relating to tax credits (House: SBs 3rd READ – INFORMAL SS SB 913)
SB1067 · 2026-05-15
Establishes the Uniform Public Expression Protection Act, which provides procedures for dismissal of actions based on public expression (House: SBs 3rd READ – INFORMAL SB 1067)
HB2576 · 2026-05-15
Creates several new state designations (House: HBs WITH SENATE AMENDMENTS SS#2 SCS HS HB 2576)
HB2576 · 2026-05-15
Creates several new state designations (House: HBs WITH SENATE AMENDMENTS SS#2 SCS HS HB 2576)
SB835 · 2026-05-15
Modifies provisions relating to court procedures (House: BILLS IN CONFERENCE CCS HCS SS SCS SBS 835 & 1111)
HB2397 · 2026-05-15
Modifies requirements for a dissolution of a public water supply district (House: HBs WITH SENATE AMENDMENTS SS HB 2397, A.A.)
HB2397 · 2026-05-15
Modifies requirements for a dissolution of a public water supply district (House: HBs WITH SENATE AMENDMENTS SS HB 2397, A.A.)
HB2292 · 2026-05-15
Modifies provisions relating to abuse and neglect reporting, including a requirement to report companion animal abuse (House: HBs WITH SENATE AMENDMENTS SS#2 SCS HCS HB 2292, A.A.)
HB2292 · 2026-05-15
Modifies provisions relating to abuse and neglect reporting, including a requirement to report companion animal abuse (House: HBs WITH SENATE AMENDMENTS SS#2 SCS HCS HB 2292, A.A.)
HB2292 · 2026-05-15
Modifies provisions relating to abuse and neglect reporting, including a requirement to report companion animal abuse (House: HBs WITH SENATE AMENDMENTS SS#2 SCS HCS HB 2292, A.A.)
SJR87 · 2026-05-15
Modifies provisions relating to sheriffs (House: BILLS IN CONFERENCE CCS HCS SS SJR 87)
SB973 · 2026-05-15
Creates and modifies provisions relating to real estate transactions (House: BILLS IN CONFERENCE CCS HCS SS SCS SB 973)
HB2474 · 2026-05-15
Modifies provisions governing design-build contracts (House: HBs WITH SENATE AMENDMENTS SCS HCS HB 2474, A.A.)
HB2474 · 2026-05-15
Modifies provisions governing design-build contracts (House: HBs WITH SENATE AMENDMENTS SCS HCS HB 2474, A.A.)
SB1421 · 2026-05-15
Modifies provisions relating to public safety (House: BILLS IN CONFERENCE CCS SS SB 1421, E.C.)
SB1421 · 2026-05-15
Modifies provisions relating to public safety (House: BILLS IN CONFERENCE CCS SS SB 1421, E.C.)
SB1408 · 2026-05-15
Increases the maximum speed limit from 70 to 75 miles per hour on rural interstates and freeways (House: BILLS CARRYING REQUEST MESSAGES SB 1408)
SB1572 · 2026-05-14
Modifies provisions relating to public employee retirement systems (House: SBs 3rd READ – INFORMAL HCS SB 1572, A.A.)
HB1840 · 2026-05-14
Establishes an alert system to assist in the location of missing persons with developmental disabilities (House: HBs WITH SENATE AMENDMENTS SS#2 SCS HCS HB 1840)
HB1840 · 2026-05-14
Establishes an alert system to assist in the location of missing persons with developmental disabilities (House: HBs WITH SENATE AMENDMENTS SS#2 SCS HCS HB 1840)
SB1019 · 2026-05-14
Modifies several provisions relating to health care (House: SBs 3rd READ – INFORMAL HCS SB 1019, A.A.)
SB1019 · 2026-05-14
Modifies several provisions relating to health care (House: SBs 3rd READ – INFORMAL HCS SB 1019, A.A.)
SB1019 · 2026-05-14
Modifies several provisions relating to health care (House: SBs 3rd READ – INFORMAL HCS SB 1019, A.A.)
SB1019 · 2026-05-14
Modifies several provisions relating to health care (House: SBs 3rd READ – INFORMAL HCS SB 1019, A.A.)
HB2508 · 2026-05-14
Allows for a search of the series LLC in the SoS Business Entity website and to obtain a certificate of good standing (House: HBs WITH SENATE AMENDMENTS SS SCS HCS HB 2508)
HB2508 · 2026-05-14
Allows for a search of the series LLC in the SoS Business Entity website and to obtain a certificate of good standing (House: HBs WITH SENATE AMENDMENTS SS SCS HCS HB 2508)
SB1196 · 2026-05-14
Modifies provisions relating to grants for certain workforce training programs (House: SBs 3rd READ – INFORMAL HCS SS SB 1196, A.A., E.C.)
SB916 · 2026-05-14
Modifies provisions relating to sovereign immunity (House: SBs 3rd READ – INFORMAL SS SCS SB 916)
SB1033 · 2026-05-14
Creates provisions relating to the regulation of air quality (House: SBs 3rd READ – INFORMAL SS SB 1033)
SB1196 · 2026-05-14
Modifies provisions relating to grants for certain workforce training programs (House: SBs 3rd READ – INFORMAL HCS SS SB 1196, A.A., E.C.)
HB3231 · 2026-05-14
Establishes the "Missouri Innovation, Public Safety, and Accountability Act" (House: HBs WITH SENATE AMENDMENTS SS#2 SCS HCS HBS 3231 & 2531)
HB3231 · 2026-05-14
Establishes the "Missouri Innovation, Public Safety, and Accountability Act" (House: HBs WITH SENATE AMENDMENTS SS#2 SCS HCS HBS 3231 & 2531)
HB2372 · 2026-05-14
Modifies provisions relating to health care (House: HBs WITH SENATE AMENDMENTS SS SCS HCS HB 2372, A.A.)
HB2372 · 2026-05-14
Modifies provisions relating to health care (House: HBs WITH SENATE AMENDMENTS SS SCS HCS HB 2372, A.A.)
HB1740 · 2026-05-14
Modifies provisions relating to driving while intoxicated (House: HBs WITH SENATE AMENDMENTS SS SCS HB 1740)
HB1740 · 2026-05-14
Modifies provisions relating to driving while intoxicated (House: HBs WITH SENATE AMENDMENTS SS SCS HB 1740)
SB975 · 2026-05-14
Modifies provisions relating to ambulance districts (House: BILLS IN CONFERENCE CCS HCS SS SB 975)
HB2596 · 2026-05-13
Modifies provisions relating to health benefit plans (House: BILLS IN CONFERENCE CCS SS HCS HB 2596)
Complete voting record from LegiScan (showing the 60 most recent of 404 total roll-call votes this session).
Primary Office
Sources:
Follow Mike Costlow
One email a week, only when there’s something: every time they broke with their party, and the closest votes they cast. Free, and you can stop any time.