Montana debt payoff calculator

What the tool compares

Two payments, side by side: what you pay now, and what you would pay with a little more added. For each it works out how long the debt takes to clear and what the interest comes to, then shows the difference between them.

That difference is the point. A payoff date on its own is a fact. A payoff date next to the one you could have instead is a decision.

A worked example, using the tool's own defaults

The calculator opens on $18,000 of total debt at an average APR of 19.9%, a current payment of $450, and $150 of extra you could add.

The extra $150 a month takes two years and one month off the term and saves about $4,950. Over the shorter term you would put in $6,300 more of your own money and hand over $4,950 less in interest, which is close to a dollar back for every dollar redirected.

The reason it works so hard is the rate. At 19.9%, interest on $18,000 runs at $299 a month before a dollar of principal moves. The first $299 of any payment is standing still. Everything above it is progress, and $600 makes twice the progress $450 does.

A second example, at different inputs

Smaller balance, higher rate: $9,500 at 22.9%, paying $260 now with $100 more available.

Interest on $9,500 at 22.9% runs at about $181 a month, so $260 leaves about $79 of progress in the first month and $360 leaves about $179. The extra $100 more than doubles the rate at which the balance falls, which is why a payment 38% larger takes more than two years off the term.

That is the general shape of it. The closer the current payment sits to the monthly interest, the more each extra dollar is worth, because the extra is being measured against the small remainder rather than against the whole payment.

When does a payment stop being enough?

When it drops to the interest charged that month, which on this balance is $299.

If both the current payment and the boosted one fall at or below that figure, the tool stops and says neither payment clears this debt. It does not print a date. There is no honest date to print: the balance is flat or rising, so no amount of waiting retires it.

This is the most useful output the tool has, because it changes what you should do next. When the payment is above the interest, the answer is arithmetic and patience. When it is below, more patience makes things worse, and the useful next step is a consolidation loan, a balance transfer or a non-profit credit counsellor, not a bigger number typed into a calculator.

The refusal, worked out

On the default figures the interest is $298.50 a month, so the boundary sits between $298 and $299. It is worth seeing what happens on either side of it.

A single dollar moves the answer from never to thirty-two years, and thirty-two years at that cost is not a plan either. The refusal is a hard edge on a soft problem: the band immediately above it stays bad for a long way up.

If your payment sits in the first three rows, more discipline is not the missing ingredient. What changes those numbers is a lower rate or a smaller balance: a consolidation loan, a promotional transfer rate, hardship terms agreed directly with the lender, or a management plan through a non-profit credit counselling agency. Those are four different actions with different consequences for your credit file, and the CFPB and FTC material in our sources sets out what each one involves before you commit to any of them.

Avalanche or snowball?

The tool assumes one blended rate across everything you owe, which means its answer is deliberately conservative. Real payoff is faster, because in reality the extra should go to one debt at a time.

Avalanche puts every spare dollar on the highest rate first, then rolls that payment into the next highest. It costs the least in interest and finishes soonest. It is the mathematically correct answer.

Snowball clears the smallest balance first regardless of rate, then rolls that payment forward. It costs more, sometimes considerably more, and it produces a closed account early, which is a real and repeatable motivation.

The gap between them is narrower than the argument suggests, and it depends on the shape of your debts rather than on principle. If the smallest balance is also the highest rate, the two plans are the same plan. If the highest rate sits on the largest balance, avalanche can run for a year before anything closes, and that is the case where snowball's early win is worth paying something for.

What both share is the rolled payment, and that is the part doing the work. When one debt clears you keep sending the same total each month and add the freed payment to the next debt on the list. The amount leaving your account never falls until everything is gone, which is why the last debts clear so much faster than the first. A plan where the total payment drops each time a balance closes is a different and much slower plan.

The tool's own caveat settles the argument better than most articles do: the cheapest plan you abandon is worth less than the plan you finish. If avalanche will hold your attention for four years, run avalanche. If it will not, snowball at a slightly higher cost beats a spreadsheet you stop opening in March.

Either way, list every debt with its balance and rate before you start. A single blended figure hides which debt is doing the damage.

What to do before adding the extra

The extra payment is the most expensive money in your budget to get wrong. Two checks first:

• Keep a small cash buffer. Clearing a card to zero and then meeting a car repair on the same card is a round trip that costs a transfer of interest and nothing else. A few weeks of expenses in a high-yield savings account keeps the payoff moving in one direction.
• Take the employer retirement match first. A match is an immediate return that no consumer debt rate exceeds.

Beyond those, the ordering is straightforward: the highest rate first, always, and stop borrowing while the plan runs. The tool assumes nothing new is borrowed, and that assumption is doing more work than any other input.

When a bigger payment is not the answer

Three situations where the answer sits outside this calculator:

1. The payment cannot clear the interest. Covered above. Consolidation, a transfer, or counselling.
2. The rate is the problem rather than the payment. A balance transfer with a 0% period, or a fixed-rate personal loan at a lower rate, changes the arithmetic in a way an extra $50 cannot. Our comparison of a personal loan against a credit card covers the trade.
3. The debt is in collections or default. Different rules apply and the CFPB has the authoritative guidance. A payoff schedule is not the immediate question.

Be wary of anything sold as debt settlement or debt relief for an up-front fee. A non-profit credit counselling agency is a different thing from a debt settlement company, and the difference matters.

The mistakes that stretch the timeline

Believing the minimum payment is making progress. At 19.9% on $18,000 the interest alone runs at $299 a month, so a payment anywhere near that figure is buying time rather than reducing anything.

Treating a payment just above the interest as a plan. $299 does technically clear the default balance, in 32 years and 5 months and at $98,311 of interest, which is not an outcome anyone would choose deliberately.

Working from one blended rate and then splitting the extra across every account. The tool computes a single payment stream and its own caveat says real payoff is faster, because the extra belongs on the highest rate until that debt is gone.

Averaging the rates instead of weighting each one by its balance. A small expensive debt disappears inside a large cheap one, and the answer that comes back is flattering rather than useful.

Letting the total payment fall as each balance closes. The rolled payment is the part doing the work, and a plan where the monthly total shrinks every time a card clears is a much slower plan.

Carrying on borrowing while the plan runs. The model assumes nothing new is added, and that is the assumption it is least able to survive.

How to check this against your statements

The inputs here are only as good as the list behind them, and that list takes half an hour to build once:

• Every balance, from the current statement. Not the credit limit, not the amount originally borrowed, and not last year's figure.
• Every rate, as a number rather than a range. Card statements show an APR for each balance type. A promotional rate should be recorded with the date it ends, because the debt gets more expensive on that date whether or not you notice.
• Every minimum. The sum of the minimums is the floor of any plan, and the current payment you enter should be the total you actually send across all accounts, not one account's payment.
• A blended rate, if you want one figure. Weight each rate by its balance rather than averaging the rates, or a small expensive debt disappears inside a large cheap one and the answer comes out flattering.

Then check the direction of travel. Add the balances up again next month. If the total has not fallen by roughly what the plan predicted, something is still being charged to one of the accounts, and that is the assumption this model is least able to survive.

The list to build before you start

One sitting with the statements, and the output stops being a guess about a guess.

• Write every debt on its own line with the current statement balance, its own APR and its own minimum, rather than one blended figure.
• Mark which debt carries the highest rate, and make that the one the extra payment goes to first.
• Record the end date of any promotional rate, and the rate it reverts to on that date.
• Add the minimums together and confirm the payment you enter is at least that total across every account, not one account's payment.
• Weight each rate by its balance when you want a single blended figure, instead of averaging the rates.
• Check each statement for whether the APR is variable, since a rise moves the payoff date without you doing anything.
• Add the balances up again next month and confirm the total fell by roughly what the plan predicted.

The limits of this model

Its caveats are short and each one is real:

1. One blended rate across every debt. Real payoff is faster, because the extra should go to the highest rate first. Read the output as a floor.
2. Avalanche against snowball is not modelled. The tool computes one payment stream, not an ordering.
3. Nothing new is borrowed while this runs. The most fragile assumption in the model.

Add to those: it assumes a fixed rate, when most card debt is variable and moves with the prime rate. It assumes payments arrive on time, so it shows no late fees or penalty APRs. And it treats the final month as a full payment, which overstates the total by a few dollars.

None of that changes the shape of the answer. It does mean the output is an estimate of a plan, not a promise about a balance. The credit card payoff calculator handles a single card in more detail, and every tool we publish is listed in the calculator index, with our sourcing set out in the methodology.