Montana: Rent Increase Notice Requirements

Montana's ordinary state-law framework

Montana does not prescribe a general notice period, amount cap, frequency
limit, or mandatory form for an ordinary residential rent increase. Under MCA
§ 70-24-201(1), the rental agreement may include rent, the term, and other
lawful provisions governing the parties. Subsections (2) and (3) address the
rent payable when the agreement is silent and the time and place for payment,
but supply no general unilateral increase procedure.

What trips people up

The seven- and 30-day periods in MCA § 70-24-441 terminate periodic
tenancies. Subsection (1) concerns a week-to-week termination, and subsection
(2) concerns a month-to-month termination. Subsection (3) confirms that the
tenancy terminates on the designated date. None says that the notice changes
rent while the tenancy continues.

For a fixed term, read the agreed rent and adjustment language. Section
70-24-201(1) confirms that the agreement may set rent and term; subsection
(2)(f) separately addresses damages for an early no-cause termination. These
provisions do not create a general mid-term rent-increase mechanism.

Retaliation is a distinct protection. Under § 70-24-431, an increase after
the listed code complaints, written landlord complaint, or tenant organizing
may be retaliatory. The statute supplies a possession defense and incorporates
§ 70-24-411 remedies, including up to three months' periodic rent or treble
damages, whichever is greater.

Common questions

Does Montana require 30 days' notice of a rent increase?

No general state statute says so. The 30-day written notice in §
70-24-441(2) terminates a month-to-month tenancy rather than changing rent.

Is there a statewide percentage cap?

No general statewide percentage or CPI formula applies to the ordinary
tenancy covered here. The rental agreement and any applicable local rule must
be checked.

What can a tenant do about a retaliatory increase?

If § 70-24-431 applies, the tenant has a possession defense and the remedies
incorporated from § 70-24-411. The protected conduct and six-month
presumption must still be evaluated.

Statutes and sources

• MCA § 70-24-201. Agreed rent, term, payment, and default tenancy rules.
  Official statute
  (accessed July 12, 2026).
• MCA § 70-24-441. Written notices terminating weekly and monthly
  tenancies.
  Official statute
  (accessed July 12, 2026).
• MCA §§ 70-24-431 and 70-24-411. Retaliatory increases, defense, and
  incorporated remedies.
  Official retaliation statute
  and official remedies statute
  (accessed July 12, 2026).