The Montana surplus lines tax is 2.75% of the premium, collected by the surplus lines producer from the insured and remitted to the Commissioner of Securities and Insurance.1Montana Legislature. Montana Code 33-2-311 – Tax on Surplus Lines Insurance A 0.175% transaction fee applies to every placement, and policies that include fire coverage carry an additional 2.5% fire tax on the fire portion of the premium.2Montana Commissioner of Securities and Insurance. Surplus Lines Montana only collects when it is the insured’s home state.
What Gets Taxed and at What Rate
The base rate is 2.75% of the premium, the same rate Montana applies to admitted insurers under Montana Code 33-2-705. One line of business gets a break: legal professional liability insurance placed on a surplus lines basis is taxed at 0.75%.3Montana State Legislature. Montana Code 33-2-705 – Report on Premiums and Other Matters, Tax on Premiums Attorneys buying malpractice coverage through a non-admitted carrier pay the reduced rate.
Two charges sit on top of the premium tax:
- A 2.5% fire tax applies when the policy covers fire risks, but only to the fire premium portion. On a commercial property policy with a $10,000 fire premium component, that is an extra $250 beyond the 2.75% levy on the full premium.2Montana Commissioner of Securities and Insurance. Surplus Lines
- A 0.175% SLIP+ transaction fee applies to the total premium. The authorizing statute lets the commissioner set this fee at up to 1% by rule, so the current rate can change without legislative action.2Montana Commissioner of Securities and Insurance. Surplus Lines4Montana State Legislature. Montana Code 33-2-321 – Stamping Fee and Clearinghouse Processing Fee
What Counts as Premium
The 2.75% applies to the net premium charged for the surplus lines policy, but two categories drop out of the taxable base. Producer fees are excluded: Montana lets surplus lines producers charge a flat fee of up to $50 on personal lines and $100 on commercial lines, and those amounts are not part of the premium for tax purposes.5Montana Legislature. Montana Code 33-2-320 – Surplus Lines Insurance Producer Fee Pass-through taxes are also excluded: amounts collected from the insured specifically to cover state and federal taxes above the base premium do not feed into the computation.1Montana Legislature. Montana Code 33-2-311 – Tax on Surplus Lines Insurance
Everything else the insurer charges as part of the policy cost is in the taxable premium. If an invoice bundles coverage premium with insurer service charges, the combined total (minus the two exclusions) is what gets taxed.
When Montana Can Collect
Montana can only tax a surplus lines placement when it is the insured’s home state. The federal Nonadmitted and Reinsurance Reform Act bars every other state from taxing the same transaction, so even if the covered property spans five states, only the home state collects.6Office of the Law Revision Counsel. 15 USC Chapter 108 – State-Based Insurance Reform The home state is where the insured maintains its principal place of business, or for an individual, the state of principal residence. If 100% of the insured risk sits outside that state, the home state shifts to whichever state receives the largest share of the taxable premium; for affiliated groups on one policy, the home state follows the member with the largest premium allocation.7Office of the Law Revision Counsel. 15 USC 8206 – Definitions
The reverse is worth stating plainly. If Montana is not the home state, the commissioner cannot collect any premium tax or stamping fee, even when the policy covers risks physically located in Montana.1Montana Legislature. Montana Code 33-2-311 – Tax on Surplus Lines Insurance
How and When to Pay
As of January 1, 2026, all surplus lines filings, endorsements, cancellations, and tax payments in Montana go through SLIP+ for States, the platform managed by the Commissioner of Securities and Insurance.8Montana Commissioner of Securities and Insurance. More Information – Section: Surplus Lines Producers enter policy data, upload supporting documentation, and submit tax payments by ACH debit through the platform. SLIP+ handles the 2.75% premium tax calculation (or 0.75% on legal professional liability), the fire tax on qualifying policies, and the 0.175% transaction fee.2Montana Commissioner of Securities and Insurance. Surplus Lines
Premium taxes are due annually, though the state accepts quarterly payments. The 0.175% transaction fee is due quarterly regardless.2Montana Commissioner of Securities and Insurance. Surplus Lines Producers paying premium tax quarterly can line the two up and submit together.
Missing a deadline can trigger penalties and disciplinary action from the Commissioner’s office. The tax is collected from the insured, but the producer is the one who must remit it and file the transaction data. Open filings from the 2025 tax year should be reviewed for accuracy before the records close; corrections go to the CSI Surplus Lines team at 406-444-2020 or producerlicensing@mt.gov.
A Note on Exempt Commercial Purchasers
Federal law lets certain large commercial insureds skip Montana’s diligent search requirement, which normally forces a producer to try at least three admitted carriers writing the line before going to the surplus lines market.9Montana State Legislature. Montana Code 33-2-302 – Home State Exclusive Authority, Conditions Precedent The exemption is procedural. The premium tax, transaction fee, and fire tax still apply at the same rates.7Office of the Law Revision Counsel. 15 USC 8206 – Definitions