Mortgage Recast Amortization Schedule: Before and After
A recast replaces your amortization schedule with a new one that starts from the smaller balance and ends on the same date. On a $300,000 loan at 4.5% with 25 years left, a $50,000 lump sum moves the first payment from $1,667.50 to $1,389.58, and the first month of interest from $1,125.00 to $937.50.
The tables below show the first payment split and the balance and interest for every year, with and without the recast.
What changes in the schedule
Fannie Mae describes a recast as a re-amortization of the new outstanding balance over the remaining term. The rate and the end date stay the same. Only the starting balance and the payment change.
The first payment, before and after
| Before recast | After recast | |
|---|---|---|
| Starting balance | $300,000 | $250,000 |
| Monthly payment (P&I) | $1,667.50 | $1,389.58 |
| Interest in the first payment | $1,125.00 | $937.50 |
| Principal in the first payment | $542.50 | $452.08 |
The lump sum goes to principal first, so the recast loan starts with less interest each month. Its first payment pays down $452.08 of principal, against $542.50 before.
Year by year: balance and interest
The example loan: $300,000, 4.5%, 25 years left, $50,000 lump sum. The balance is the amount left at the end of each year.
| Year | Balance, no recast | Balance, recast | Interest, no recast | Interest, recast |
|---|---|---|---|---|
| 1 | $293,354 | $244,462 | $13,364 | $11,137 |
| 2 | $286,403 | $238,669 | $13,059 | $10,882 |
| 3 | $279,132 | $232,610 | $12,739 | $10,616 |
| 4 | $271,528 | $226,273 | $12,405 | $10,338 |
| 5 | $263,574 | $219,645 | $12,056 | $10,047 |
| 6 | $255,254 | $212,712 | $11,691 | $9,742 |
| 7 | $246,553 | $205,461 | $11,308 | $9,424 |
| 8 | $237,452 | $197,876 | $10,909 | $9,091 |
| 9 | $227,932 | $189,943 | $10,491 | $8,742 |
| 10 | $217,975 | $181,646 | $10,053 | $8,378 |
| 11 | $207,561 | $172,968 | $9,596 | $7,997 |
| 12 | $196,669 | $163,891 | $9,117 | $7,598 |
| 13 | $185,276 | $154,397 | $8,617 | $7,181 |
| 14 | $173,359 | $144,466 | $8,094 | $6,745 |
| 15 | $160,896 | $134,080 | $7,546 | $6,288 |
| 16 | $147,859 | $123,216 | $6,974 | $5,811 |
| 17 | $134,224 | $111,853 | $6,375 | $5,312 |
| 18 | $119,962 | $99,969 | $5,748 | $4,790 |
| 19 | $105,046 | $87,538 | $5,093 | $4,244 |
| 20 | $89,444 | $74,536 | $4,408 | $3,673 |
| 21 | $73,125 | $60,937 | $3,691 | $3,076 |
| 22 | $56,056 | $46,713 | $2,941 | $2,451 |
| 23 | $38,203 | $31,836 | $2,157 | $1,798 |
| 24 | $19,531 | $16,276 | $1,337 | $1,114 |
| 25 | $0 | $0 | $479 | $399 |
Both schedules end at zero in year 25. Added up, the interest is $200,249 without the recast and $166,874 with it. The lump sum itself and any recast fee are not counted.
Build the schedule for your loan
The calculator below opens with the example above and shows the same kind of table and chart for the numbers you enter. For the formula behind each row, see how to calculate a recast payment.
Reading the schedule
- Lower interest each year. Every year of the recast column pays less interest, because the balance is lower all the way.
- Slower balance fall. A lower payment pays down principal more slowly. To compare with keeping the old payment and finishing early, see recast vs extra principal payment.
- Size of the drop. How much the payment falls is in how much will a recast lower my payment.
Frequently asked questions
Does a recast change my amortization schedule?
Yes. Fannie Mae describes a recast as a re-amortization of the new outstanding balance over the remaining term. The old schedule is replaced by a new one that starts from the smaller balance and ends on the same date.
Why is less of my first payment interest after a recast?
Interest each month is the balance times the monthly rate. A smaller balance means less interest, so the same kind of payment is split differently. In the example the first month's interest falls from $1,125.00 to $937.50.
Does the loan end on the same date?
Yes. Both schedules on this page reach zero after 25 years. The recast keeps your remaining term, so only the payment and the balance in between change.
Where can I see a schedule for my own loan?
The calculator on this page builds the yearly principal and interest table for the balance, rate, years left and lump sum you enter. Your servicer's recast agreement shows the official new payment.
Does the schedule include escrow?
No. A principal and interest schedule leaves out taxes and insurance, which your servicer collects in escrow.
How is the yearly interest worked out?
Each month, interest is the balance times the yearly rate divided by 12. The payment minus that interest reduces the balance. Add the twelve months to get the year.
Sources
Every figure on this page comes from the pages below. Checked 2026-10-16. Rules change, so confirm with your own servicer.
- Fannie Mae: Recast Loan Overview (the new balance is re-amortized over the remaining term)
- Wikipedia: Amortization calculator (the payment and interest formulas)
More recast guides
- Free Mortgage Recast Calculator - enter your own loan and see the new payment.
- Recast vs Refinance Calculator - Compare both options on the same loan, with a break-even point.
- Recast Fees and Rules by Lender - Fees, minimums and loan limits published by four large lenders.
- How to Calculate a Recast Payment - The formula, a step-by-step example and the numbers to check.
- How Much Will a Recast Lower My Payment? - The lump sum divided by balance shortcut, with lookup tables.
- Recast vs Extra Principal Payment - The same lump sum two ways: payment, payoff date and interest.