Does Montana offer a 529 tax deduction?

Yes. Montana allows a state income tax deduction for 529 contributions up to $3,000 per taxpayer per year, or $6,000 for a married couple filing jointly who each contribute. The deduction reduces your Montana taxable income, so the dollar savings equals the deductible amount times your marginal state rate.

Can I deduct contributions to another state's 529 plan?

Yes — and this is unusual. Montana is one of the few states that lets residents deduct contributions to any state's 529 plan, not just its own Achieve Montana plan. That gives Montana savers freedom to choose a plan with lower fees or better investments while still claiming the deduction.

What is the deduction limit in Montana?

The cap is $3,000 per taxpayer annually, doubling to $6,000 for joint filers when both spouses contribute. Contributions above the cap are not deductible in Montana and there is no carryforward of the unused excess to future years, so spreading large contributions across years can capture more benefit.

How much will I actually save?

Your state tax savings equals the deductible amount multiplied by your marginal Montana rate. At the top 5.9% rate, a full $3,000 deduction saves about $177 in state tax; a joint $6,000 deduction saves about $354. The larger long-term benefit is the tax-free investment growth on the account.

Are 529 withdrawals taxed in Montana?

Withdrawals used for qualified education expenses are free of both federal and Montana income tax. Non-qualified withdrawals are taxable and may trigger recapture of previously deducted Montana contributions plus a federal penalty on earnings, so keep distributions tied to eligible education costs.

Montana 529 Plan Tax Benefit Calculator

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Achieve Montana — the state’s 529 plan — gives residents a state income tax deduction for college-savings contributions, and Montana is one of the rare states that extends that deduction to any state’s 529 plan, not just its own. The deduction is capped at $3,000 per taxpayer ($6,000 for joint filers), and your dollar savings depend on your marginal Montana rate.

How it works

The deduction lowers your Montana taxable income; the savings are that reduction times your marginal rate:

deductible    = min(contribution, cap)   // cap = $3,000 single, $6,000 joint
tax savings   = deductible × marginal rate (4.7% or 5.9%)
excess        = contribution − cap        // not deductible, no carryforward

Because Montana’s top rate is 5.9%, the maximum single-filer benefit is roughly $177 per year, and a joint couple maxing the cap saves about $354.

Example and notes

A joint-filing couple contributing $6,000 at the 5.9% rate saves about 6,000 × 0.059 = $354 in Montana income tax this year. Contributing $8,000 would still cap the deduction at $6,000 — the extra $2,000 is not deductible and cannot be carried forward. The deduction is a yearly bonus, but the larger payoff is decades of tax-free growth when withdrawals fund qualified education expenses.