Paying Off a Loan Early: When an Extra Payment Saves the Most
The questions people actually ask about paying a loan off early, answered bluntly: prepayment penalties, how lenders count interest, the Rule of 78s, and when an extra payment saves the most.
- The Prepayment line on your Truth in Lending disclosure says whether you may pay a penalty and whether you'd get part of the finance charge back.
- Paid off halfway, a hypothetical $3,000 loan at 99% APR returns about $291 less interest under the Rule of 78s than under simple interest.
- Extra money saves the most early in the loan and on the highest-APR debt, and only if the lender applies it to principal.
Is paying a loan off early worth it? Usually yes, but the same $500 can be worth $1,552 or $251 on the same loan, depending on when you send it.
That’s a hypothetical $3,000 loan at 99% APR over 24 months: $500 sent to principal after the third payment cuts about $1,552 of interest, and the same $500 after the eighteenth payment cuts about $251. How much you save also depends on how your lender counts interest, which most borrowers never check. Below are the questions people actually ask, answered bluntly, with Gabe, a hypothetical borrower, carrying the numbers.
“Will they charge me for paying it off early?”
Maybe. One line tells you. Find “Prepayment” on your Truth in Lending disclosure. Under Regulation Z it has to say, one way or the other, that you “may” or “will not” have to pay a penalty for paying early. Silence doesn’t count as “no.” Many personal loans carry no prepayment penalty, but read the line rather than assume.
Watch for penalties that don’t use the word. Regulation Z’s commentary counts a minimum finance charge on a simple-interest loan as a penalty, along with interest charged as if the balance were still owed after you’ve paid it off. If the line is unclear, ask in writing:
What to write
“If I pay this loan off in full early, will any fee, minimum finance charge or other amount be added? Please confirm in writing how interest is calculated on this loan.”
“Isn’t the interest already baked in?”
On some loans, yes, and that’s the question that decides what paying early is worth.
Simple interest is charged on the balance you still owe. Each payment covers the interest built up since the last one, and the rest lowers the balance. Pay early and future interest is never charged.
Precomputed interest is figured for the whole term on day one and built into what you owe. Pay off early and the lender refunds the “unearned” part. Federal law (15 U.S.C. 1615) requires a prompt refund of unearned interest when you prepay in full. What it doesn’t fix for most small loans is the method used to work out that refund.
How to tell which you have:
- The Prepayment line mentions a refund or rebate “of part of the finance charge”: usually precomputed.
- The contract says “precomputed,” “add-on,” “Rule of 78s” or “sum of the digits”: precomputed.
- It says “simple interest” or “interest accrues daily on the unpaid principal”: simple interest.
“What’s the Rule of 78s, and is that even legal?”
It’s a way of counting most of the interest as earned early. On a 12-month loan, the numbers 1 through 12 add up to 78. The Rule of 78s treats 12/78 of the interest as earned in month one, 11/78 in month two, and so on down to 1/78. Pay off early and you’ve “used up” more interest than a simple-interest loan would have charged, so your refund is smaller.
Legal? Depends on the loan. Federal law bans the method for precomputed consumer loans with terms over 61 months made after September 30, 1993. Most small personal loans run well under 61 months, so for them state law decides, and the rules vary. We’d rather borrow on simple interest, full stop.
“OK, how much does the counting method actually cost?”
Here’s Gabe’s loan. He borrows $3,000 at a hypothetical 99% APR for 24 months. His payment is $290.90, and if he pays on schedule the interest totals $3,981.48. This is what paying off early would cost under each method.
| Paid off after | Payoff, simple interest | Payoff, Rule of 78s | Rule of 78s costs extra |
|---|---|---|---|
| Payment 6 | $2,679.61 | $2,966.64 | $287.03 |
| Payment 12 | $2,164.09 | $2,455.50 | $291.41 |
| Payment 18 | $1,334.59 | $1,466.58 | $131.99 |
Paying off after 12 payments still saves Gabe $1,326.59 of interest under simple interest, or $1,035.18 under the Rule of 78s. Early payoff pays off either way; the method decides by how much. On a hypothetical 36% loan of the same size, the gap after 12 payments is only $37.08. The method matters most on expensive loans.
“Should I pay extra now, or wait until I have more?”
Now, if the loan is simple interest. An extra payment saves the most early in the loan and on the costliest debt, because that’s where the most interest is still waiting to be charged.
| $500 sent after | At 36% APR | At 99% APR |
|---|---|---|
| After payment 3 | $376.54 | $1,551.54 |
| After payment 12 | $182.76 | $646.86 |
| After payment 18 | $76.73 | $251.37 |
A steady extra $50 a month works too: on Gabe’s loan it saves $1,410.90 and ends the loan 7 months early. At 36%, the same $50 saves $373.94 and ends it 6 months early. Try your own figures in the loan payment calculator.
The rules that follow from the numbers:
- Two loans? Send extra money to the higher APR first, and make the minimum on the other.
- Simple-interest loan? Send extra as soon as you have it. Waiting costs interest.
- Precomputed loan? Partial extra payments often just move your due date forward without cutting interest. If so, set the money aside and pay the loan off in full once you can.
- No savings cushion at all? Keep a small one first. Running short and borrowing again at a high rate can wipe out the savings.
- Thinking of refinancing instead? Only if the new loan’s total cost, including any fees, is lower than what’s left on this one. Compare total dollars, not payments. Our guide to what small loans cost by APR shows how fast the total grows at high rates.
“I paid extra. Why didn’t my balance drop?”
Because some lenders treat extra money as an early installment: your next due date moves out, but the principal may not drop right away. Before you send it, write:
What to write
“Please apply the extra $[amount] I’m paying today to the principal balance of loan [number], not to future installments. My regular payment schedule should stay the same.”
Then check the next statement: the principal should fall by the full extra amount.
“How do I make the last payment without getting charged again?”
Get a payoff quote with a date on it. The balance in your app is usually not the payoff amount. Interest keeps adding up until the money arrives, so ask for a payoff figure “good through” a specific date. For precomputed loans, federal law requires the lender to give you the payoff amount and any refund within 5 days of your request, in writing if you asked in writing, with one free statement a year.
- Ask for the payoff amount, the good-through date, and the daily interest after that date.
- Pay the exact amount by a method that arrives before the date.
- Ask for a “paid in full” letter and keep it.
- Cancel the automatic payment with the lender and confirm no more debits are scheduled; our guide to loan payments and your bank account shows how.
- Check your credit report a month or two later to see the account reported as paid.
And will paying it off early hurt my credit? Not much, as a rule. The account usually stays on your report as closed and paid as agreed. Some scores shift a little when an installment loan closes, in either direction. That small effect rarely outweighs the interest saved on a high-APR loan.
Find the Prepayment line on your disclosure tonight; it takes two minutes and tells you which half of this guide is about you.
About this guide. General information, not financial, legal or tax advice. Lenders set their own rates, fees and approval rules, and state law varies. Examples use hypothetical numbers, not offers. Last reviewed October 12, 2026.
