Late Fees on Invoices in Montana
What Montana contractors and small businesses need to know about charging late fees, interest rates, prompt payment laws, and mechanics lien deadlines.
Max Interest Rate
10% per annum (default legal rate); 15% maximum by contract
Small Claims Limit
$7,000
Small Claims Court (Justice Court)
Mechanics Lien Deadline
90 days from completion for GCs; 90 days from last furnishing for subs
Montana Prompt Payment Act
Montana Prompt Payment Act, Mont. Code Ann. § 28-1-905
Montana requires state agencies to pay within 30 days. Private construction follows contract terms with mechanics lien enforcement under Mont. Code Ann. § 71-3-521.
Late fee rules for Montana invoices
Montana allows contractual late fees up to the 15% maximum. The state's construction lien law provides clear timelines for filing.
Montana's default legal interest rate is 10% per annum. Written agreements may specify up to 15% per annum. Consumer transactions have additional protections.
Important disclaimer
This page provides general information about Montana late fee rules. It is not legal advice. Laws change, and your specific situation may have unique factors. For disputes involving significant amounts, consult a licensed attorney in Montana.
Demand letters and mechanics liens in Montana
Montana does not require a formal demand letter, but a 20-day preliminary notice is required for subcontractors and materialmen.
Mechanics lien deadline: 90 days from completion for GCs; 90 days from last furnishing for subs. A lien must be filed with the county clerk.
Sample late fee clause for Montana invoices
“Payment is due within the terms specified above. A late fee of 1.5% per month (10% per annum (default legal rate); 15% maximum by contract maximum per Montana law) will be applied to all balances remaining unpaid after the due date. Pursuant to Montana Code Annotated § 71-3-521 et seq. (Construction Liens), the undersigned reserves all rights to pursue collection including but not limited to mechanics lien filing, small claims action (up to $7,000 in Small Claims Court (Justice Court)), and referral to collections.”
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Start Free TrialFrequently asked questions — Montana
What is the maximum late fee I can charge on an invoice in Montana?▾
In Montana, Montana's default legal interest rate is 10% per annum. Written agreements may specify up to 15% per annum. Consumer transactions have additional protections. Always disclose late fee terms in your contract or invoice before work begins.
Does Montana have a prompt payment act?▾
Yes. Montana requires state agencies to pay within 30 days. Private construction follows contract terms with mechanics lien enforcement under Mont. Code Ann. § 71-3-521.
What is the small claims court limit in Montana?▾
The small claims court limit in Montana is $7,000. Claims are filed in Small Claims Court (Justice Court). You generally do not need an attorney for small claims.
How long do I have to file a mechanics lien in Montana?▾
In Montana, 90 days from completion for GCs; 90 days from last furnishing for subs. A lien must be filed with the county clerk.
Do I need to send a demand letter before filing a lien in Montana?▾
Montana does not require a formal demand letter, but a 20-day preliminary notice is required for subcontractors and materialmen.