What Does Re-Amortize Mean? Re-Amortization and Principal Curtailment Explained
The word your servicer uses for what everyone else calls a recast — plus what a principal curtailment actually is.
What does re-amortize mean?
To re-amortize a loan means to recalculate its payment schedule using the current balance, the existing interest rate, and the time remaining on the term. On a mortgage it is the same operation consumers call a recast: you pay a lump sum toward principal, and the lender rebuilds the amortization schedule around the smaller balance. The rate and the payoff date do not change.
- Re-amortize and recast mean the same thing. Servicers and loan documents use the first; consumers and media use the second.
- A principal curtailment is the lump-sum payment that triggers it — Fannie Mae's term, not a separate event.
- Re-amortization is a broader word than recast: it also describes what happens after a loan modification, a payment deferral, or a construction-to-permanent conversion.
- The spelling varies wildly — reamortize, re-amortize, re amortize — and they are all the same word. No difference in meaning.
The word breaks apart cleanly. Amortize comes from the Latin admortire, to kill off — an amortizing loan is one being killed off gradually by scheduled payments, as opposed to an interest-only loan where the principal survives untouched until the end. Re-amortize is simply doing that calculation again, partway through.
You will meet the term in three places: on a servicer's phone tree, in the title of Fannie Mae Form 181 (Agreement for Modification, Re-Amortization, or Extension of a Mortgage), and in spreadsheet templates built by people who work in mortgage operations rather than mortgage marketing.
How re-amortization is calculated
Re-amortization runs the standard amortization formula a second time. Nothing new is introduced:
What changes between the first run and the second is only which numbers go in:
| Input | Original amortization | Re-amortization |
|---|---|---|
| B — balance | Original loan amount | Current unpaid principal, after the curtailment |
| r — monthly rate | Rate on the note ÷ 12 | Identical — unchanged |
| n — months | Full original term | Months remaining on that term |
Because the rate and the number of remaining months are both held fixed, the payment moves in a straight line with the balance. Reduce the balance by 12.5% and the payment falls 12.5%. This linearity is a useful sanity check on any re-amortization figure you are given: divide the new payment by the old, and it should match the ratio of the new balance to the old. If it doesn't, someone has changed the term.
Enter your balance, rate, remaining years and lump sum to see the re-amortized payment — plus what the lower payment costs you in total interest.
Re-amortize your loanWhat is a principal curtailment?
If you have read anything from Fannie Mae or spoken to a servicing department, you have probably met the phrase principal curtailment. It is not a separate product or a different kind of payment. It is the industry's word for money applied to reduce your unpaid principal balance ahead of schedule.
Fannie Mae's Selling Guide defines it in exactly those terms: a principal curtailment is the application of funds used to reduce the unpaid principal balance of the mortgage loan (Selling Guide B2-1.5-05). The same topic notes that curtailments applied to reduce the monthly payment are permitted, which is the contractual basis for recasting.
The word curtail is doing honest work here — you are cutting short the life of the debt.
| Phrase | Precise meaning | Watch out for |
|---|---|---|
| Principal curtailment | Voluntary extra payment reducing your unpaid balance | Nothing — this is your own money, paid by choice |
| Principal reduction | Often means forgiven principal in a loss-mitigation context | Very different credit and tax consequences |
| Principal prepayment | Same as curtailment, in plainer language | Check whether a prepayment penalty applies |
| Re-amortization | The recalculation that may follow a curtailment | Does not happen automatically — you must request it |
Where else re-amortization shows up
Recasting is the most common reason a mortgage gets re-amortized, but it is not the only one. The word covers any mid-life recalculation of a payment schedule.
- After a loan modification. When a servicer changes the rate or term of a distressed loan, the resulting schedule is re-amortized around the new terms. Fannie Mae's Form 181 covers modification, re-amortization and extension in a single instrument for exactly this reason.
- After a payment deferral. Where missed payments are moved to the back of the loan as a non-interest-bearing balance, the remaining schedule is recalculated.
- Construction-to-permanent conversion. A construction loan that draws down over time is re-amortized when it converts to a permanent mortgage with a fixed balance.
- Adjustable-rate resets. Every time an ARM adjusts, the payment is re-amortized over the remaining term at the new rate. This one happens automatically, without any request from you — see the ARM calculator.
- Student loans and some business loans. Income-driven repayment recalculations are re-amortizations in the same technical sense.
Only the first three involve you asking for anything. The ARM case is worth internalising, because it means an adjustable-rate borrower experiences re-amortization on a schedule whether or not they know the word.
Reamortize, re-amortize, re amortize: which is right?
Search data shows people reaching for this word in a dozen shapes: reamortize, re-amortize, re amortize, reamortization, reamortizing, reamortized, and a long tail of misspellings including reammortize and reamoritize.
There is no distinction between any of them. American style guides generally prefer the closed form reamortize; legal and mortgage documents lean toward the hyphenated re-amortization, which is what appears on Fannie Mae Form 181. British usage favours re-amortise. All refer to one operation.
If you are searching your loan documents for the term, search for the stem amorti rather than a full spelling — it will catch every variant plus amortization schedule, which is where the numbers you actually want tend to live.
Common questions
What does re-amortize mean on a mortgage?
It means the lender recalculates your monthly principal and interest payment using your current balance, your existing interest rate, and the months remaining on your term. On a mortgage this is the same operation as a recast.
Is re-amortization the same as refinancing?
No, and the difference matters. Re-amortization keeps your existing loan — same note, same rate, same lender, no underwriting. Refinancing replaces the loan entirely with a new one at current market rates, with a full application and closing costs. Re-amortization typically costs $150 to $500; refinancing typically costs 2% to 5% of the loan amount. The comparison is laid out in full in recast vs refinance.
Does re-amortizing hurt your credit?
No. There is no new application, no hard inquiry and no new account. The loan continues reporting as the same tradeline with the same origination date.
Can any loan be re-amortized?
Not on request. Conventional mortgages backed by Fannie Mae or Freddie Mac generally permit it. FHA, VA and USDA loans do not. Most jumbo and portfolio loans are at the lender's discretion. Auto loans and personal loans almost never offer it. See recast requirements and eligibility for the full picture.
What is a principal curtailment on a mortgage?
Funds applied to reduce your unpaid principal balance ahead of schedule — an extra payment aimed at principal rather than at your next installment. Fannie Mae's Selling Guide B2-1.5-05 defines it in those terms. It is the trigger for a recast, but it does not cause one on its own; you have to request the re-amortization separately.
Payment figures on this page were computed from the amortization formula and checked against a full month-by-month schedule before publication. Definitions of principal curtailment and re-amortization are taken directly from Fannie Mae's Selling and Servicing Guides and from the title of Form 181, all linked below, rather than from secondary finance media.
A research-first finance team. No lead selling, no lender rankings, no affiliate-pulled recommendations. Every guide pairs primary sources (IRS, CFPB, Federal Reserve, CRA) with the free calculators you can run yourself.
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