Lease rules
Can my landlord limit my guests?
Reasonable guest policies (like limits on stays longer than 1-2 weeks) are generally enforceable. Blanket bans on visitors, or rules targeting who may visit, generally are not.
Guest clauses exist to stop unofficial move-ins, and courts respect that purpose. A rule that guests staying beyond, say, 14 days need approval is normal; a rule that you may have no overnight guests interferes with your quiet enjoyment of the home and rarely holds up.
The real risk is the long-term guest who drifts into 'unauthorized occupant' - a common default notice. If someone's staying for weeks, get ahead of it in writing.
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General educational information, not legal advice. Laws vary by state and city and change over time - for a specific situation, contact a local tenant-rights organization.