A young couple applies for your two-bedroom rental in Kalispell. Just the two of them sign the lease. Six months later, there’s a third car in the driveway, a name you don’t recognize on a package, and what looks a lot like a third adult living there full time. Could you have set a lower occupancy limit from the start to prevent this? And now that it’s happened, what can you actually do?
Occupancy is one of those areas where landlords assume there’s a hard legal number somewhere, and are surprised to learn it’s more of a balancing test than a rule. Here’s how it actually works.
No Montana Statute Sets a Specific Number
Unlike security deposits or entry notice, occupancy isn’t something the Montana Residential Landlord and Tenant Act addresses directly. Instead, the framework landlords and fair housing agencies actually rely on comes from federal guidance: a 1998 HUD memo commonly known as the “two-plus-one” formula — two people per bedroom, plus one additional occupant. Under this guideline, a two-bedroom rental could reasonably house up to five people (2 × 2 + 1).
This isn’t a hard cap you’re legally required to enforce to the letter. It’s a benchmark that HUD and fair housing agencies generally treat as presumptively reasonable — meaning a landlord who applies it is unlikely to be found in violation of fair housing law for doing so. But it’s a starting point for judgment, not a rigid formula that applies identically to every unit.
Why You Can’t Just Pick a Stricter Number
This is where the discrimination protections we covered in what a landlord cannot do in Montana become directly relevant. The federal Fair Housing Act protects “familial status” as a category, and Montana’s own Human Rights Act (Mont. Code Ann. §49-2-101 et seq.) reinforces the same protection at the state level. That means you can’t set an occupancy policy that has the effect of excluding families with children, even without intending to discriminate.
Say you decide a one-bedroom unit can only house two people, full stop, no exceptions. That policy might look neutral on paper, but if it effectively bars a parent with two young children from renting a one-bedroom (three people total — still within the two-plus-one guideline), you could be facing a fair housing complaint. HUD’s own guidance specifically cautions against occupancy policies stricter than two-plus-one without a legitimate, non-discriminatory justification behind them.
What Can Legitimately Adjust the Number
Two-plus-one is a guideline, not a rigid formula, and several factors can reasonably push a reasonable occupancy figure up or down for a specific unit:
- The size of the unit and its bedrooms. A “two-bedroom” with two small bedrooms and 750 square feet is a different situation than one with 1,500 square feet.
- The age of children in the household. HUD’s guidance notes that a family with several very young children may reasonably occupy a smaller space than a similarly sized family with older kids needing more privacy.
- The layout of the unit, including whether there’s a den, office, or bonus room that functions like an extra bedroom.
- Septic, well, or water system capacity, and local building and health codes — genuinely relevant in parts of Flathead County served by septic and well systems rather than municipal utilities, and a legitimate, health-and-safety-based reason to set a lower occupancy figure that has nothing to do with discrimination.
A good-faith occupancy policy grounded in unit size, local building or health codes, and genuine safety considerations holds up. A policy designed, even unintentionally, to discourage families with children does not — regardless of how neutrally it’s worded.
The “Guest Who Never Leaves” Situation
Back to the scenario at the top of this article: this is one of the most common occupancy headaches for Montana landlords. A tenant’s partner, sibling, or adult child moves in gradually, without ever being added to the lease. The legal distinction that matters here is between a long-term occupant who has effectively become a resident and someone who’s genuinely just visiting.
If you suspect this is happening, changing the locks or confronting the person directly isn’t the answer — remember, self-help remedies are illegal under Montana law. Instead:
- Check your lease. A well-drafted lease should define a maximum occupancy and require any additional long-term occupant to be added and screened, just like the original tenants.
- Document what you’re actually observing — additional vehicles, mail, or reasonable observations during a properly noticed visit under MCA §70-24-312.
- Communicate with the tenant in writing, referencing the specific lease clause, and give them the chance to either add the occupant (with screening) or resolve the situation.
- If it doesn’t resolve, and the tenant is genuinely violating a valid lease term, you may have grounds to move toward ending the tenancy — but this needs to be handled through the proper legal process, not on your own initiative.
Building a Defensible Occupancy Policy Into Your Lease
Rather than reacting to overcrowding after the fact, the stronger approach is setting clear occupancy terms in the lease from day one. A solid occupancy clause should:
- State a specific maximum number of occupants for the unit, based on something like the two-plus-one guideline adjusted for the unit’s actual size and layout
- Require that any occupant staying beyond a defined period (commonly 14–30 days) be disclosed and, if an adult, added to the lease and screened
- Apply the same way to every tenant, regardless of family status
That last point is where fair housing complaints most often actually originate — not from the policy itself, but from inconsistent enforcement. One tenant’s growing household gets flagged, another’s doesn’t, and the difference happens to track a protected characteristic. Applying your occupancy standard the same way across every unit, whether it’s in Kalispell, Whitefish, or Columbia Falls, is what keeps a reasonable policy legally defensible.
Putting a Real Occupancy Clause Into Your Lease
Here’s roughly what a defensible occupancy clause looks like in practice, adjusted for the property in question:
> “This unit shall be occupied by no more than [X] persons. Any adult occupant residing in the unit for more than [14/30] consecutive days must be disclosed to the landlord in writing and, if approved, added to this lease following the landlord’s standard screening process.”
The specific number you fill in should reflect the two-plus-one guideline as a starting point, then be adjusted based on the actual size and layout of that particular unit — not copied uniformly across every property you own regardless of square footage. A studio and a three-bedroom house shouldn’t carry the same flat number just because it’s convenient to standardize your lease template.
Why This Trips Up Self-Managing Landlords
Occupancy issues rarely arrive as one dramatic event. They build slowly — a “temporary” guest who becomes permanent, a newborn who wasn’t on the original application, an adult child who moves back home after a job loss. Most landlords don’t want to be the bad guy about a reasonable increase in household size, and most of the time, it genuinely isn’t worth addressing. The legal exposure shows up when occupancy grows well past what the unit can reasonably support, and the landlord either ignores it (creating wear-and-tear and habitability strain) or handles it inconsistently across different tenants (creating fair housing exposure).
A Note on Short-Term and Vacation Rentals
Occupancy questions look a little different for vacation rentals, which are common across the Flathead Valley given the proximity to Glacier National Park and Flathead Lake. Short-term rental occupancy is typically governed by the booking platform’s terms and your own listing rules rather than the same fair-housing framework that applies to long-term residential leases, since a short-term guest isn’t establishing residency in the same legal sense a long-term tenant is. That said, local ordinances in Kalispell, Whitefish, and Columbia Falls may impose their own occupancy caps tied to short-term rental permitting, separate from anything discussed above — worth checking directly with the relevant city or county office if vacation rentals are part of your portfolio.
Getting the Balance Right
This is one of those areas where the right call is rarely “as strict as possible” or “don’t worry about it” — it’s a genuinely fact-specific judgment that benefits from having seen the pattern play out across a lot of leases and a lot of different tenant situations. If you’d rather not be the one making these calls property by property, our property management services include drafting and enforcing occupancy standards that are both legally sound and consistently applied — protecting you on both fronts, from overcrowded units and from fair housing exposure.
Not sure whether your current occupancy policy would hold up if challenged? Get in touch with our team — we help Kalispell-area owners set lease terms that are fair, defensible, and consistently enforced.
