New Montana laws taking effect May 13, 2025

50 laws take effect May 13, 2025.

Of the 778 bills enacted since 2025, 774 have an effective date and 4 don't yet (listed below). A law here takes effect that day by its main provisions; parts of a staggered act may take effect on other dates.

Updated Oct 31, 2026 at 11:39 a.m. EDT.

Government (10)

  • HB 480 · 2025 Regular SessionPublished

    Revise when a party in a proceeding is entitled to jury trial

    How we got this date

    Published by the legislature: All Sections: 2025-05-13.

    How effective dates are worked out

  • HB 592 · 2025 Regular SessionPublished

    Generally revise agency rulemaking under MAPA

    How we got this date

    Published by the legislature: All Sections: 2025-05-13.

    How effective dates are worked out

  • HB 680 · 2025 Regular SessionPublished

    Generally revise trade and commerce laws

    How we got this date

    Published by the legislature: All Sections: 2025-05-13.

    How effective dates are worked out

  • HB 692 · 2025 Regular SessionPublished

    Generally revise the SMART Act

    How we got this date

    Published by the legislature: All Sections: 2025-05-13.

    How effective dates are worked out

  • HB 786 · 2025 Regular SessionPublished

    Revise Montana arts council chair responsibilities

    How we got this date

    Published by the legislature: All Sections: 2025-05-13.

    How effective dates are worked out

  • HB 819 · 2025 Regular SessionPublished

    Revise laws relating to flag displays in and on state buildings and grounds

    How we got this date

    Published by the legislature: All Sections: 2025-05-13.

    How effective dates are worked out

  • SB 260 · 2025 Regular SessionPublished

    Provide for alteration of service district boundaries

    How we got this date

    Published by the legislature: All Sections: 2025-05-13.

    Parts of this act take effect on other dates.

    How effective dates are worked out

  • SB 301 · 2025 Regular SessionPublished

    Generally revise utility lines and facilities laws

    How we got this date

    Published by the legislature: All Sections: 2025-05-13.

    How effective dates are worked out

  • SB 316 · 2025 Regular SessionPublished

    Revising disability retirement provisions for MPORS and FURS

    How we got this date

    Published by the legislature: All Sections: 2025-05-13.

    How effective dates are worked out

  • SB 553 · 2025 Regular SessionPublished

    Generally revise state policy laws

    How we got this date

    Published by the legislature: All Sections: 2025-05-13.

    How effective dates are worked out

Taxes (10)

  • HB 231 · 2025 Regular SessionDerived

    Revise property tax rates for certain property

    How we got this date
    Except as provided in subsections (2) and (3), [this act] is effective on passage and approval.

    Signed by the Governor May 13, 2025 → takes effect on that day May 13, 2025

    Parts of this act take effect on other dates.

    How effective dates are worked out

  • HB 329 · 2025 Regular SessionPublished

    Make the Montana ammunition act permanent

    How we got this date

    Published by the legislature: All Sections: 2025-05-13.

    How effective dates are worked out

  • HB 424 · 2025 Regular SessionPublished

    Revise taxes for class 17 data center property

    How we got this date

    Published by the legislature: All Sections: 2025-05-13.

    How effective dates are worked out

  • HB 483 · 2025 Regular SessionPublished

    Revise laws to reduce property taxes while preserving the current 95 school equalization mills

    How we got this date

    Published by the legislature: All Sections: 2025-05-13.

    Parts of this act take effect on other dates.

    How effective dates are worked out

  • HB 845 · 2025 Regular SessionPublished

    Increase IRC 529 education savings income tax deduction

    How we got this date

    Published by the legislature: All Sections: 2025-05-13.

    How effective dates are worked out

  • HB 846 · 2025 Regular SessionPublished

    Revising property taxation for certain local government subdivisions

    How we got this date

    Published by the legislature: All Sections: 2025-05-13.

    How effective dates are worked out

  • SB 326 · 2025 Regular SessionPublished

    Generally revise laws related to MEDIA Act film tax credits

    How we got this date

    Published by the legislature: All Sections: 2025-05-13.

    How effective dates are worked out

  • SB 333 · 2025 Regular SessionPublished

    Repeal sunset on coal washing credit

    How we got this date

    Published by the legislature: All Sections: 2025-05-13.

    How effective dates are worked out

  • SB 542 · 2025 Regular SessionDerived

    Generally revise property tax laws

    How we got this date
    Except as provided in subsections (2) and (3), [this act] is effective on passage and approval

    Signed by the Governor May 13, 2025 → takes effect on that day May 13, 2025

    Parts of this act take effect on other dates.

    How effective dates are worked out

  • SB 550 · 2025 Regular SessionPublished

    Revise taxation of of certain telecommunications property

    How we got this date

    Published by the legislature: All Sections: 2025-05-13.

    How effective dates are worked out

Crime (7)

  • HB 117 · 2025 Regular SessionPublished

    Establish criminal justice data warehouse priorities

    How we got this date

    Published by the legislature: All Sections: 2025-05-13.

    How effective dates are worked out

  • HB 833 · 2025 Regular SessionPublished

    Provide funding to increase correctional capacity

    How we got this date

    Published by the legislature: All Sections: 2025-05-13.

    How effective dates are worked out

  • HB 954 · 2025 Regular SessionPublished

    Extend PL280 termination date

    How we got this date

    Published by the legislature: All Sections: 2025-05-13.

    How effective dates are worked out

  • SB 393 · 2025 Regular SessionPublished

    Provide funding for enforcement of PL 280

    How we got this date

    Published by the legislature: All Sections: 2025-05-13.

    How effective dates are worked out

  • SB 413 · 2025 Regular SessionPublished

    Criminalize disclosure of certain explicit AI-generated media

    How we got this date

    Published by the legislature: All Sections: 2025-05-13.

    How effective dates are worked out

  • SB 429 · 2025 Regular SessionPublished

    Generally revise laws related to determination and restoration of fitness in criminal proceedings

    How we got this date

    Published by the legislature: All Sections: 2025-05-13.

    How effective dates are worked out

  • SB 69 · 2025 Regular SessionPublished

    Revise county attorney reporting requirements for child sexual abuse

    How we got this date

    Published by the legislature: All Sections: 2025-05-13.

    How effective dates are worked out

Healthcare (3)

  • SB 430 · 2025 Regular SessionPublished

    Generally revise laws related to civil commitment and emergency detention of mentally ill persons

    How we got this date

    Published by the legislature: All Sections: 2025-05-13.

    Parts of this act take effect on other dates.

    How effective dates are worked out

  • SB 497 · 2025 Regular SessionPublished

    Provide laws related to healthcare provider burnout

    How we got this date

    Published by the legislature: All Sections: 2025-05-13.

    How effective dates are worked out

  • SB 535 · 2025 Regular SessionPublished

    Revise laws related to experimental treatments

    How we got this date

    Published by the legislature: All Sections: 2025-05-13.

    How effective dates are worked out

Public Lands (3)

Civil Rights (2)

Climate (2)

  • HB 623 · 2025 Regular SessionPublished

    Revise laws relating to nuclear energy

    How we got this date

    Published by the legislature: All Sections: 2025-05-13.

    How effective dates are worked out

  • HB 923 · 2025 Regular SessionDerived

    Revise categorical exclusions from nondegradation authorization

    How we got this date
    Except as provided in subsection (2), [this act] is effective on passage and approval.

    Signed by the Governor May 13, 2025 → takes effect on that day May 13, 2025

    Parts of this act take effect on other dates.

    How effective dates are worked out

Education (2)

Elections (2)

  • HB 818 · 2025 Regular SessionPublished

    Ban foreign funding for ballot measures

    How we got this date

    Published by the legislature: All Sections: 2025-05-13.

    How effective dates are worked out

  • SB 226 · 2025 Regular SessionPublished

    Require petition submittals be dropped off within a specific timeframe

    How we got this date

    Published by the legislature: All Sections: 2025-05-13.

    How effective dates are worked out

Housing (2)

  • HB 505 · 2025 Regular SessionPublished

    Allow Montana housing infrastructure revolving loan fund to retain its interest and income and provide for fund transfers

    How we got this date

    Published by the legislature: All Sections: 2025-05-13.

    How effective dates are worked out

  • HB 876 · 2025 Regular SessionPublished

    Sawmill revitalization act

    How we got this date

    Published by the legislature: All Sections: 2025-05-13.

    How effective dates are worked out

Mining and Drilling (2)

Traffic (2)

  • HB 940 · 2025 Regular SessionDerived

    Prohibit overnight camping on state highway right-of-way

    How we got this date
    Except as provided in subsection (2), [this act] is effective on passage and approval.

    Signed by the Governor May 13, 2025 → takes effect on that day May 13, 2025

    Parts of this act take effect on other dates.

    How effective dates are worked out

  • SB 545 · 2025 Regular SessionPublished

    Establish the Danny L. Radish Highway in Lincoln County

    How we got this date

    Published by the legislature: All Sections: 2025-05-13.

    How effective dates are worked out

Affordability (1)

Finance (1)

  • HB 898 · 2025 Regular SessionDerived

    Generally revise laws related to LLC operating agreements

    How we got this date
    Except as provided in subsection (2), [this act] is effective on passage and approval.

    Signed by the Governor May 13, 2025 → takes effect on that day May 13, 2025

    Parts of this act take effect on other dates.

    How effective dates are worked out

Wages (1)

  • HB 667 · 2025 Regular SessionPublished

    Revise labor laws relating to employers and public service

    How we got this date

    Published by the legislature: All Sections: 2025-05-13.

    How effective dates are worked out

Enacted, but not yet dated (4)

These laws' texts tie their dates to something outside the legislative record (Contingent), or not enough is recorded yet to give one (Unresolved). They may take effect May 13, 2025 too; the record doesn't say.

Show all 4
  • HB 447ContingentEnact the Respiratory Care Interstate CompactEffective on the date the compact is legislatively enacted into law by the seventh member state
  • HB 56ContingentEstablish ambulance provider assessment fee programApproval by the United States department of health and human services of all waivers and approvals necessary to implement the assessment fee and supplemental payments
  • SB 233ContingentAdopting the interstate massage compactCompact legislatively enacted into law by the seventh member state
  • SB 279ContingentAdopt the dietitian licensure compactThe compact has been legislatively enacted into law by the seventh member state.