Can a landlord charge for a pet in Montana, and what does the law require for an assistance animal?

Yes, with no statutory limit.

No Montana statute mentions a pet deposit, and Montana sets no cap on a residential security deposit of any kind, so there is no ceiling for a pet deposit to sit inside or on top of. What the state has instead is a definition that catches the charge whatever it is called: a security deposit is value given to secure the payment of rent or payment for damage to and cleaning of the premises, any deposit the lease requires the tenant to provide or maintain in effect for part or all of the term is presumed to be a security deposit, and 'a fee or charge for cleaning and damages, no matter how designated, is presumed to be a security deposit' (section 70-25-101, subsection 4). A pet deposit or a so-called non-refundable pet fee for cleaning or damage therefore goes into the deposit machinery: it is refundable except for the statutory deductions, it cannot be waived away in the lease (section 70-25-103), and the 30-day and 10-day return deadlines apply. The statute sets no per-animal figure and no multiplier. The only charge exemption in Montana law is for a service animal and it comes from outside the deposits chapter (section 49-4-214, subsection 2); an emotional support animal has no state charge exemption.

Refundability: A pet charge that answers the description in section 70-25-101, subsection 4, is a security deposit, and a security deposit is refundable except for the deductions the statute allows: damage alleged to have been caused by the tenant, unpaid rent, late charges, utilities, penalties due under the lease, other money owing at the time of deduction, and actual cleaning expenses including a reasonable charge for the landlord's labor (section 70-25-201, subsection 1). Nothing else may be withheld: 'A person may not deduct or withhold from the security deposit any amount for purposes other than those set forth in this section' (subsection 4). A lease term contrary to the chapter, and any tenant waiver of it, is invalid (section 70-25-103), so calling a pet charge non-refundable in the lease does not make it so.

Yes — no statute caps, authorizes or forbids pet rent or a pet fee.

Montana sets no figure and no ceiling for pet rent or a pet fee, and has no general non-refundable-fee rule to reach one. The label does not decide the question, the function does: a pet charge for cleaning or damage is presumed to be a security deposit no matter how it is designated, is refundable except for the deductions in section 70-25-201, subsection 1, and cannot be contracted out of (sections 70-25-103 and 70-24-202, subsection 1). A straightforward monthly pet rent falls outside that presumption and is left to the agreement (section 70-24-201, subsection 1). There is no reasonableness standard on pet charges; the only fee prohibition in the landlord-tenant chapter is unrelated to animals, barring an extra fee based on the rent payment type except to recoup an electronic bank fee (section 70-24-201, subsection 4). For an assistance animal, state law bars an extra charge only where the animal is a service animal (section 49-4-214, subsection 2).

Monthly pet rent: A recurring monthly charge for the privilege of keeping an animal is left to the rental agreement. It is not caught by the security-deposit presumption, which reaches a charge for cleaning and damages and a deposit the tenant must provide or maintain in effect for part or all of the term, and no other Montana statute reaches it. Section 70-24-201, subsection 1, lets a landlord and a tenant include any term not prohibited by the chapter or by other law, including rent.

A one-time pet fee: A one-time pet fee is decided by what it is for, not by what the lease calls it. If it is a fee or charge for cleaning and damages it is presumed to be a security deposit under section 70-25-101, subsection 4, and must be handled as one. Montana has no general bar on non-refundable fees: the words non-refundable and nonrefundable do not appear anywhere in chapter 70-24 or chapter 70-25. Application fees are on their own page.

No — but a written-rules or mid-term-change provision would govern a pet rule the landlord adopts.

No Montana statute requires a lease to say whether pets are allowed, and none supplies an answer when the lease is silent, so the pet term is whatever the parties agree (section 70-24-201, subsection 1). A silent lease does not become a no-restrictions lease. What the state does regulate is the landlord's rule-making power and the notice owed when a rule changes mid-tenancy, set out above. One pet figure sits in the eviction ladder and is worth knowing: where the tenant's noncompliance involves an unauthorized pet the notice period is 3 days, against the 14-day period for noncompliance generally, and the tenancy does not end if the tenant fixes the problem before the date in the notice; a repeat of substantially the same noncompliance within 6 months can be terminated on 5 days' notice (section 70-24-422, subsection 1). No statute limits how many animals a tenant may keep; the only per-animal clause requires information for each animal where a tenant asks to keep more than one emotional support animal (section 70-24-114, subsection 3). Montana has no pet mandate for publicly financed or income-restricted housing.

Changing the rule mid-tenancy: A landlord may adopt a rule about the tenant's use and occupancy of the premises, and a pet rule is such a rule. It binds the tenant only if its purpose is to promote the convenience, safety or welfare of the occupants, preserve the property from abusive use or fairly distribute services, it is reasonably related to that purpose, it applies to all occupants fairly, it is explicit enough to tell the tenant what to do, it is not a way of evading the landlord's own obligations, and the tenant had notice of it when signing or when it was adopted. Every rule must be in writing and given to each tenant, including each new tenant on arrival. A rule adopted after signing that works a substantial modification of the tenant's bargain is not valid until 7 days after written notice in a week-to-week tenancy or 30 days after written notice in a month-to-month tenancy (section 70-24-311, subsections 1 to 3). Notice is given the way section 70-24-108 provides.

Yes.

Montana law says nothing about a landlord's breed, size or weight rule for pets: it neither bars one nor authorizes one, and there is no assistance-animal exception to a breed rule because there is no breed rule to except. The word breed does not appear in the landlord-tenant chapter, the deposits chapter, the mobile home lot chapter, the Human Rights title or the criminal code, and size and weight are never used of an animal in them. The nearest thing to an animal-characteristic rule is individual, not categorical: a landlord may deny a request for an emotional support animal where that animal poses a direct threat to the safety or health of others, or a direct threat of physical damage to the property, that cannot be reduced or eliminated by another reasonable accommodation (section 70-24-114, subsection 2). Cities and counties may control dogs, including vicious dogs, under the local-government title, but that is animal-control law and is not authority to write a landlord's pet policy, which section 7-1-111, subsection 13, forbids. Montana has no statute barring an insurer from underwriting on dog breed.

Yes — a state statute or rule sets what a landlord may request or what a certifier must meet for an assistance animal in housing. The operative rules are statutory. State law incorporates a federal statute or codified regulation by reference.

A tenant with a disability or a disability-related need for an emotional support animal may request, and be approved by a landlord, to keep one as a reasonable accommodation in housing (section 70-24-114, subsection 1). The landlord's powers under the section all open with the words 'unless otherwise prohibited by federal law, rule, or regulation'. Where the disability-related need is not readily apparent the landlord may request supporting information that reasonably supports the need for the particular animal; may require proof of compliance with state and local licensing and vaccination requirements for each animal; and may deny the request where the animal poses a direct threat to the safety or health of others, or a direct threat of physical damage to the property, that cannot be reduced or eliminated by another reasonable accommodation (subsection 2). Where a tenant asks to keep more than one animal, the information must be supplied for each (subsection 3). The landlord must issue a written determination after receiving the supplemental information, and give it the way section 70-24-108 requires (subsection 4). The section does not apply to a service animal (subsection 8), and it does not restrict existing federal or state law on reasonable accommodation and equal access to housing (subsection 9). Alongside it, a person with a disability who has or obtains a service animal is entitled to full and equal access to housing accommodations and may not be required to pay extra compensation for the animal (section 49-4-214, subsection 2), and refusing a reasonable accommodation in rules, policies, practices or services needed to give a person with a disability equal opportunity to use and enjoy a housing accommodation is an unlawful discriminatory practice (section 49-2-305, subsections 4 and 5). Mobile home lot rentals have the same documentation section at 70-33-110 with one extra subsection, stated as a separate row below.

Who it binds: Montana runs two scopes and they do not match. The documentation statute is part of the landlord-tenant act, so it binds every landlord of a dwelling unit under that act: no owner-occupied exemption, no unit threshold, no small-landlord carve-out, subject only to the eight excluded arrangements in section 70-24-104. Section 70-33-110 does the same job for mobile home lot rentals. The fair-housing and disability-rights routes are narrower. The Human Rights Act excludes the rental of sleeping rooms in an owner-occupied private residence designed for single-family occupancy where the owner rents no more than three of them (section 49-2-305, subsection 2), and the disabilities chapter excludes from a housing accommodation any single-family residence whose occupants furnish for compensation not more than one room (section 49-4-203, subsection 1). A small owner-occupied landlord outside both of those can still owe the documentation duties.

The landlord may request supporting information only where the tenant's disability-related need for the animal is not readily apparent, and then only information 'that reasonably supports the tenant's need for the particular emotional support animal being requested' (section 70-24-114, subsection 2). The landlord may not request information that discloses a diagnosis or the severity of the tenant's disability, or any medical records relating to it, although the tenant may volunteer that material (subsection 4). Proof of compliance with state and local licensing and vaccination requirements may be required for each animal (subsection 2).

A licensed or qualified professional may certify, and the text names other sources too. A treatment relationship is required. An online certificate is not, by itself, sufficient. A caregiver, reliable third party or agency may supply it. The certifier's own rule requires a relationship with the person of at least thirty days before writing the documentation. A landlord may not require medical records, a diagnosis or its severity. The landlord must answer the request in writing, with no deadline stated. A landlord may require proof of vaccination or licensing compliance.

Who may certify: Either of two sources, and since October 1, 2025 they are genuine alternatives rather than a pair that must both be met. The first is a health care practitioner with personal knowledge of the tenant's disability, acting within the scope of practice, whose information identifies the particular assistance or therapeutic emotional support the specific animal provides and states the effective date, license number and type of professional license held. That practitioner must be a mental health professional licensed in Montana under section 53-21-102, subsection 12: a certified professional person, a physician, a clinical professional counselor, a psychologist, a clinical social worker, a psychiatric mental health advanced practice registered nurse, a psychiatric mental health physician assistant, or a marriage and family therapist. The second is 'information from any other source that the landlord determines to be reliable in accordance with the federal Fair Housing Act and Title 49, chapter 2' (section 70-24-114, subsection 2). Widely repeated summaries that describe Montana as requiring a 30-day relationship of the tenant are wrong on that point: the 30 days is a condition on the practitioner's qualification, and the second route does not use a practitioner at all.

The relationship test: Beyond the 30 days, the practitioner must have completed a clinical evaluation of this tenant about the need for an emotional support animal, must have personal knowledge of the tenant's disability, and must be acting within the scope of the license or certificate held (section 70-24-114, subsections 2 and 10).

The certifier's duties: A practitioner who supplies the information must be a mental health professional licensed in Montana, must have held a client-provider relationship with the tenant for at least 30 days before supplying it, must have completed a clinical evaluation of the tenant about the need for the animal, must act within the scope of the license, must have personal knowledge of the disability, must identify the particular assistance or therapeutic emotional support the specific animal provides, and must state the effective date, license number and type of the license held (section 70-24-114, subsections 2 and 10). A practitioner may be disciplined by the licensing board for a violation of the section (subsection 7); the licensing title supplies the hooks, making it unprofessional conduct to sign or issue a professional document the licensee knows or reasonably ought to know contains a false or misleading statement, and to violate a law or rule relating to the conduct of the profession (section 37-1-316, subsection 1).

Montana writes more of this down than most states. A landlord may ask for supporting information only where the need is not readily apparent, and may never ask for a diagnosis, the severity of a disability or medical records. The information may come from a mental health professional licensed in Montana who has known the tenant as a client for at least 30 days, has completed a clinical evaluation about the need for the animal, has personal knowledge of the disability, and gives the effective date, number and type of the license, identifying what the specific animal does for the tenant. Since October 1, 2025 that is one route and not the only one: the landlord may instead accept information from any other source the landlord finds reliable. A registration of any kind, including an identification card, patch, certificate or similar registration obtained electronically or in person, is not by itself enough to establish the need. The landlord may require proof of licensing and vaccination for each animal, and must issue a written determination once the supplemental information is in, although the statute fixes no deadline for it. Montana says nothing about telehealth, nothing about annual re-evaluation and nothing about a prescribed form.

Under state law, yes — the state bar reaches only a trained service, guide, hearing or assistance dog, or a certified animal; the federal rules still govern an emotional support animal; the bar is an express no-extra-charge clause, in a statute.

A person with a disability who has or obtains a service animal 'may not be required to pay extra compensation for the service animal but is liable for any damage done to the premises by the service animal' (section 49-4-214, subsection 2). That is the whole of Montana's charge protection, and it has stood in this shape since 1971 as amended in 2019; the 2025 service-dog act did not touch it. It reaches only a dog or miniature horse individually trained to assist a person with a disability, because the term expressly excludes an emotional support animal, and the emotional support animal statute itself contains no charge clause of any kind: its only money sentence makes the tenant liable for damage. So under state law a landlord may charge a pet deposit or pet rent for an emotional support animal, and what protection exists comes from elsewhere. The federal section of the 50-state page carries the federal layer.

The definition it hangs on: 'Service animal' means a dog or miniature horse individually trained to provide assistance to an individual with a disability. The term does not include an emotional support animal (section 49-4-203, subsection 2).

The tenant is liable for damage the animal causes like any other tenant, by express words.

Liability is stated expressly on both sides, and the emotional support animal limb is wider than the usual formula. A tenant with a disability-related need for an emotional support animal 'is liable for any damage done to the premises or to another person on the premises' by that animal (section 70-24-114, subsection 6). A person with a service animal 'is liable for any damage done to the premises by the service animal' (section 49-4-214, subsection 2), and a handler training a service animal takes the same rights and the same responsibilities (subsection 3).

An offense or sanction that reaches a misrepresentation made to obtain housing: licensing discipline, reaching the certifier who signs.

Montana is the national outlier here: the only sanction that reaches housing falls on the professional who signs, not on the tenant. A health care practitioner may be subject to disciplinary action from the practitioner's own licensing board for a violation of the emotional support animal section (section 70-24-114, subsection 7, and section 70-33-110, subsection 7, for mobile home lots), and the licensing title makes it unprofessional conduct to sign or issue a professional document the licensee knows or reasonably ought to know is false or misleading, and to violate a law relating to the conduct of the profession. No prior warning is needed and the statute states no figure. On the tenant's side there is nothing: the criminal code creates no offense of misrepresenting an animal as an assistance or support animal, and the misrepresentation sections in the disabilities chapter fire only where a person misrepresents an animal to get into the public places and public accommodations listed in section 49-4-211 - inns, restaurants, hotels, motels, taverns, campgrounds, transportation and the like - which is a business-premises list that does not include rental housing. Those public-accommodation sections carry a misdemeanor after a prior written warning, with fines of $50 for a first offense, $75 to $200 for a second and $100 to $1,000 for a third or later, and possible community service; they are not the housing offense and do not reach a landlord. A tenant who fakes an assistance animal to a Montana landlord commits no Montana offense; the landlord's remedies are the lease and the eviction ladder.

Who enforces it: The licensing board that issued the practitioner's license enforces the housing limb; there is no prosecution, no fine and no private action attached to it in the statute. The unprofessional-conduct provisions the board applies are in section 37-1-316, subsection 1.

In part — state law preempts the kinds of local rule named as barred, and any power named is one state law grants.

Montana takes pet rules in housing away from its cities. A local government unit with self-government powers is denied any power that applies to or affects landlords where the power would license them or regulate their dealings with tenants beyond the landlord-tenant act, the deposits chapter and the mobile home lot act, and any power to deviate from or add to the exclusive application of those three chapters (section 7-1-111, subsection 13). Such a unit may not act inconsistently with state law in an area the state has taken for itself, and a standard lower or less stringent than the state's counts as inconsistent (section 7-1-113). A unit without self-government powers holds only the powers the Legislature grants it, and the county-powers section grants no power over landlords. What is devolved is animal control: counties and municipalities may control dogs, vicious dogs and barking dogs, license dogs and control animals running at large. The distinction answers the question readers actually ask - a city may regulate the dog, but it may not regulate the landlord's tenancy terms. No Montana city is known to have a pet-in-housing ordinance, and given the denial of powers one would be an outlier.

The whole landlord-tenant field occupied: A local government unit with self-government powers may not exercise any power that applies to or affects landlords, as the landlord-tenant act and the mobile home lot act define them, where the power is intended to license landlords or to regulate their dealings with tenants beyond what those chapters provide, and may not deviate from or add to the exclusive application of the landlord-tenant act or the mobile home lot act. A city therefore cannot write its own pet-policy rule for private rentals. Text: MCA § 7-1-111 · (13)(a), (13)(b)(i), (13)(b)(iii).

Local deposit or fee rules barred: The same denial of powers names the residential tenants' security deposit law: a self-government unit may not deviate from or add to its exclusive application, so a local pet-deposit or pet-fee ceiling is outside local power. Text: MCA § 7-1-111 · (13)(b)(ii).

Local rent control barred: A local government unit is also denied any power to control the amount of rent charged for private residential or commercial property, which is separate from the pet rules and is stated here so the two are not confused. Text: MCA § 7-1-111 · (26).