Paying Extra on a Mortgage: Where It Goes and What It Buys | HL Hunt
Paying Extra on a Mortgage: Where It Goes and What It Buys
The payment is the same every month and what it does changes completely. On a $312,000 loan at 6.55%, the first payment is 14.1% principal and payment 181 is 37.5%, which is why early extra payments are worth so much more than late ones. An extra $100 a month saves $62,236 and finishes the loan 47 months early, which is about two dollars of interest removed per extra dollar paid. Here is the arithmetic, and what to check before doing it.
What you'll learn
Where your payment actually goes
On a $312,000 mortgage at 6.55% over 30 years, the payment is $1,982.32 and the same every month. What it is doing changes completely.
| Payment | To interest | To principal | Share to principal |
|---|---|---|---|
| First payment | $1,703.00 | $279.32 | 14.1% |
| Payment 181 (year 16) | $1,238.21 | $744.12 | 37.5% |
That is why extra payments early are worth so much more than extra payments later. A dollar of principal removed in month one removes 30 years of interest on that dollar. The same dollar in year 25 removes five.
Total interest over the full term is about $401,636, which is more than the amount borrowed. Per our pricing analysis, that is the arithmetic of a long term at that rate rather than anything unusual about the loan.
What extra principal buys
| Extra per month | Total interest | Interest saved | Term | Paid off earlier by |
|---|---|---|---|---|
| Nothing | $401,636 | 360 months | ||
| $100 | $339,400 | $62,236 | 313 months | 47 months |
| $200 | $295,682 | $105,955 | 279 months | 81 months |
| $300 | $262,865 | $138,771 | 252 months | 108 months |
That two-to-one ratio is the figure worth carrying around, and it falls as the loan ages. The same $100 started in year ten buys considerably less, because the interest it is removing has fewer years left to accrue. Per our reversibility analysis, this is one of the few household financial decisions where acting early compounds rather than merely helps.
Biweekly schemes, demystified
Paying half the monthly amount every two weeks is marketed as a clever structural trick. It is an extra payment with extra steps.
- 26 half-payments a year equals 13 monthly payments rather than twelve
- That extra payment is $1,982.32 a year, which is $165.19 a month in equivalent terms
- The benefit is the extra payment, not the fortnightly timing, which contributes a small amount at most
So a biweekly plan that charges a setup or service fee is charging you to do something you can do free by adding $165 to your monthly payment, and per our intermediary analysis the fee is the reason the product is marketed as a mechanism rather than described as an extra payment.
There is one real advantage: the fortnightly schedule matches a fortnightly pay cycle, and per our timing analysis aligning an obligation to when money arrives genuinely reduces the chance of a miss. If that is the reason, it is a good reason, and it does not require paying a third party to arrange.
Make sure it is applied to principal
An extra amount paid without instruction may be held as a prepayment of the next scheduled payment rather than applied to principal, which produces none of the benefit above. Send it as a separate payment marked for principal, or set the instruction on the account, and then check the next statement to confirm the principal balance fell by the full extra amount. This is the single most common way extra payments fail to do anything.
Check these before paying extra
Extra principal is a good use of money and rarely the best one, and the comparison is not close in several common cases.
- Higher-rate debt first. Per our card interest analysis, a card balance at 24% returns far more than reducing a mortgage at 6.55%.
- An emergency buffer first. Per our buffer analysis, principal paid into a house is not available in a bad month, and the household that needs it then borrows at a worse rate.
- Employer retirement matching first, where it exists, because a match is an immediate return no interest rate competes with.
- Mortgage insurance removal, which may be reachable with a smaller amount than you expect and removes a monthly cost entirely rather than reducing interest.
- Check for a prepayment penalty, which is uncommon on current residential mortgages and not unknown, and is stated in the note.
- Compare against the rate honestly. Reducing a 6.55% loan is a guaranteed 6.55% return, which is good and is not the highest available in every situation.
Item two is the one that reverses the decision most often. Per our liquidity analysis, equity is the least accessible form of household wealth, so a household that puts its buffer into principal has converted liquid money into illiquid money and will meet its next shock with credit instead.
Item four is worth checking rather than assuming. Where mortgage insurance is being paid, reaching the threshold that removes it eliminates a payment rather than reducing a balance, which is frequently a larger monthly improvement than the interest saved by the same amount of principal.
What determines the rate on the next one
Paying down a loan does not build the payment record that prices your next one. HL Hunt Personal Credit Builder reports a revolving account in your name each month, so the file keeps developing while the balance comes down.
Recast against refinance against extra payments
| Option | What it changes | When it fits |
|---|---|---|
| Extra principal, same payment | Shortens the term, payment unchanged | You want the loan gone and can afford the payment |
| Recast after a lump sum | Recalculates the payment downward over the remaining term | You want a lower payment, and a small fee is usually charged |
| Refinance | New rate, new term, closing costs | Rates have fallen enough to cover the costs, per our refinancing analysis |
| Nothing | Keeps the money liquid | The rate is low relative to alternatives, or the buffer is thin |
The second row is the option most borrowers do not know exists. A recast takes a lump sum you have already decided to pay and converts it into a permanently lower monthly payment over the original term, rather than a shorter term at the same payment. Per our variance analysis, a lower fixed obligation reduces the number of months a household can fall short in, which for a household with variable income is frequently worth more than finishing the loan earlier.
And the two are a genuine choice rather than a right answer. Extra payments at an unchanged amount minimize total interest; a recast minimizes monthly exposure. A household optimizing total cost should not recast and a household optimizing resilience should, and nobody will ask which you are doing.
Frequently asked questions
The first payment is 14.1% principal and payment 181 is 37.5%. A dollar removed early cancels thirty years of interest on itself; later it cancels five.
$62,236 of interest and 47 months, for $31,300 of extra payments. Roughly two dollars of interest removed per extra dollar paid, falling as the loan ages.
The extra payment is worth having; the fee is not. It is 13 monthly payments a year, equal to adding $165.19 a month, which you can do free.
Paying extra without marking it for principal, so it is held as a prepayment of the next instalment and does nothing. Verify on the next statement.
Key takeaways
- The first payment on a $312,000 loan at 6.55% is 14.1% principal; by payment 181 it is 37.5%.
- An extra $100 a month saves $62,236 of interest and 47 months, roughly two dollars saved per extra dollar paid.
- That ratio falls as the loan ages, which is why early extra payments compound and late ones merely help.
- A biweekly plan is thirteen monthly payments a year, equivalent to adding $165.19 a month, which you can do without a fee.
- Mark extra amounts for principal and verify on the statement, because unmarked extras may be held as prepayments and do nothing.
- Higher-rate debt, an emergency buffer, and any employer match all outrank reducing a 6.55% loan.
- Removing mortgage insurance eliminates a payment rather than reducing a balance, which is often the larger monthly improvement.
- A recast converts a lump sum into a lower payment over the original term, which suits resilience where extra payments suit total cost.
This guide is educational and does not constitute financial, tax, or mortgage advice. All figures are stylized illustrations using an assumed balance, rate, and term, computed on a standard amortization basis, and do not describe any particular loan. Prepayment application rules, recast availability and fees, prepayment penalties, mortgage insurance removal thresholds, and the treatment of extra payments vary by lender and by loan agreement. Read your own note and consult your servicer and a qualified adviser before making additional payments.