Accelerated Payment Calculator

What the Accelerated Payment Calculator does

This calculator lays out all six Canadian mortgage payment frequencies side by side — monthly, semi-monthly, bi-weekly, accelerated bi-weekly, weekly and accelerated weekly — and shows the true payment, the actual payoff period and the total interest for each one at your rate and amortization.

Every non-monthly figure is derived the way Canadian lenders actually derive it: from the monthly payment first, never solved independently against the amortization formula. For the two accelerated frequencies the shortened amortization is solved directly rather than assumed, because the real payoff date does not land on a clean number of years.

• The payment amount at all six frequencies
• The actual payoff period for each, correctly shortened for the two accelerated options
• Total interest over the life of the mortgage at each frequency
• Interest saved and time saved switching from your current frequency to another
• The honest other half: how much more you actually pay across a year to get that saving

The variables that move the answer — and how lenders treat them

Two inputs do almost all the work here, and lenders treat both very differently from how a borrower experiences them.

• Payment frequency — this changes nothing about your rate and everything about your payoff date. Accelerated bi-weekly pays half the monthly amount 26 times a year, which is mathematically 13 monthly payments instead of 12: one extra full payment a year, applied entirely to principal. Plain bi-weekly and semi-monthly simply repackage the same annual amount into more, smaller payments and save comparatively little.
• Mortgage amount and rate — these set the monthly baseline every other frequency is derived from. A larger mortgage or a higher rate means a larger dollar saving, though the shape of it — roughly three to four years off a 25-year amortization — stays fairly consistent across typical mortgage sizes.
• Rate type — a fixed rate compounds semi-annually by law, a variable rate compounds monthly at most lenders. That changes the periodic rate slightly and therefore every payment figure on this page.
• Lenders qualify you on the monthly-equivalent payment whichever frequency you actually choose, so switching frequency never changes how much mortgage you can be approved for. It only changes how quickly you clear what you already have.

How payment frequencies are actually calculated in Canada

The monthly payment is calculated first, using the standard Canadian formula with semi-annual compounding for a fixed rate: P × i ÷ (1 − (1 + i)^−N), where i is the periodic rate implied by the compounding convention and N is the amortization in months.

Every other frequency is then derived from that monthly figure. Semi-monthly is half the monthly payment, paid 24 times a year. Plain bi-weekly and weekly scale the annual total down to the new number of periods, so the amount paid across a year is unchanged from monthly — these do not accelerate payoff meaningfully. The two accelerated frequencies keep the monthly payment amount but split it in half for bi-weekly, or in quarter for weekly, which raises the annual amount paid by roughly one extra monthly payment.

Because an accelerated payment no longer matches what a clean schedule would produce, the true number of periods to reach a zero balance is solved directly rather than assumed. A payment even slightly larger than the interest accruing each period pays off strictly faster than dividing the stated amortization by the new frequency would suggest.

• Monthly baseline: P × i ÷ (1 − (1 + i)^−N)
• Semi-monthly: monthly ÷ 2, paid 24 times a year
• Bi-weekly and weekly, not accelerated: monthly × 12 ÷ n — the same annual total as monthly
• Accelerated bi-weekly: monthly ÷ 2, paid 26 times a year — 13 monthly payments’ worth annually
• Accelerated weekly: monthly ÷ 4, paid 52 times a year — the same effect
• Actual payoff period: solved from the payment and the periodic rate, never assumed

What this is worth, and what lenders actually offer

Nearly every Canadian lender offers all six frequencies at no cost, and most allow a change at any time rather than only at renewal. That makes this one of the very few mortgage decisions that costs nothing to implement and can be reversed if your cash flow changes.

• Interest saved — a genuine saving from clearing principal faster, not a lender promotion
• Time saved — typically three to four years off a 25-year amortization moving from monthly to accelerated bi-weekly
• Extra paid per year — the honest other half: the saving is funded by roughly one extra monthly payment a year
• The payment at each frequency — useful for matching your mortgage to a bi-weekly or weekly pay cheque, separately from whether you accelerate it

Using your results well

If your budget can absorb it, accelerated bi-weekly is usually the highest-value, lowest-effort change available on a mortgage: no renegotiation, no penalty, no change in rate. Compare it against plain bi-weekly or semi-monthly above to see how much of the benefit comes from the acceleration itself rather than simply from paying more often.

What this does not model is a change in rate, term or lender — it holds those constant and isolates frequency alone. It also assumes every scheduled payment is made in full and on time; missed or reduced payments move the payoff date.

• Match the frequency to your pay cheque first, then decide separately whether to accelerate it
• Confirm with your lender whether a change is free and how much notice it needs
• Pair this with a lump-sum prepayment to combine the two most effective free ways to clear a mortgage faster
• Remember the saving is funded by paying more each year, not by a lower rate