What this calculator answers
Switching to bi-weekly payments is often described as a trick for paying off a mortgage faster. The real saving comes from the word "accelerated". An accelerated bi-weekly payment is half of your monthly payment, taken 26 times a year. That is 13 monthly payments a year instead of 12, and the extra month goes straight to principal.
A regular bi-weekly payment is set so you pay about the same each year as monthly. It saves a little, because the money arrives sooner, but not much. This calculator puts all six frequencies side by side so you can see the difference in dollars.
How the calculation works
- Every option uses the same balance, rate and amortization, with Canadian semi-annual compounding for fixed rates (monthly is available for variable).
- Monthly, semi-monthly, bi-weekly and weekly payments are each calculated to pay off the mortgage over the full amortization at the rate per payment period.
- Accelerated bi-weekly and weekly take the monthly payment and divide it by 2 or 4.
- Each option is simulated payment by payment until the balance reaches zero. Interest saved is the monthly total interest minus that option's total.
- The last row shows monthly payments with one-twelfth added. It pays the same yearly amount as accelerated bi-weekly, which shows the saving comes from paying more, not from the calendar.
Assumptions and limits
- The rate you enter is an example. It is held the same for the full amortization, although in practice you renew every term.
- No prepayments, missed payments or payment holidays are included.
- How each frequency is calculated is lender policy. Most Canadian lenders follow the method used here; a few differ.
- Changing your payment frequency mid-term is usually allowed, but some lenders charge a fee or limit how often you can change. Check your contract.
Common questions
Is bi-weekly the same as twice a month?
No. Semi-monthly means 24 payments a year, usually on fixed dates such as the 1st and 15th. Bi-weekly means every two weeks, which is 26 payments a year.
Why does accelerated bi-weekly save so much?
Because you pay more. Half your monthly payment 26 times a year adds up to one extra monthly payment each year, and all of it reduces your balance.
Can I get the same saving without changing frequency?
Usually, yes. Raising your monthly payment by about one-twelfth gives nearly the same result. Most lenders let you increase your payment within your prepayment privileges. The prepayment calculator shows other ways to pay extra.
Should I match my payments to my paycheque?
It often makes budgeting easier. If you are paid every two weeks, accelerated bi-weekly lines up with your pay and builds in the extra payment without much effort.
Sources
- Interest Act, section 6 (rules checked 2026-10-31)