The law in plain English
Return deadline
Under Mont. Code Sections 70-25-101 to 70-25-206, the deposit response usually has to be sent within 30 days of the move-out timeline described by the state rule.
Required notice
Montana generally does not impose a statewide deposit cap, and the landlord usually has 10 days to return the deposit if nothing is withheld or 30 days to send the refund and itemized statement when deductions are claimed.
This dispute type
Once the Montana deadline passes, the dispute stops being only about the deductions and becomes a deadline-compliance problem too. A landlord may still argue damage existed, but Mont. Code §§ 70-25-101 to 70-25-206 sets the clock for returning the balance and explaining any amount withheld.
Penalty leverage
If the withholding was wrongful or in bad faith, the exposure allowed under the statute is: Landlord forfeits the right to retain any portion of the deposit