Mortgages & MoneyLive

Bi-Weekly Mortgage Calculator

Compare a standard monthly mortgage with paying half every two weeks. Because there are 26 fortnights in a year, you make the equivalent of 13 monthly payments — the extra one cuts years off the term.

Short answer

Bi-weekly payments make the equivalent of one extra monthly payment per year, often shaving 4–6 years off a 25-year mortgage and saving 15–25% of the total interest.

Mortgage

Loan amount

Interest rate

Original term

yrs

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Calculation method, coverage and version

Inputs used: Loan amount, Interest rate, Original term.
Calculation approach: The calculator applies the rules and assumptions described in “How it works” to the values you enter. Rounding can cause small differences from an official or provider calculation.
Coverage: Mortgages & Money. UK nations, tax treatment, local rules and provider criteria can differ; check the official sources shown below before acting.
Content version: No page-specific review date is currently published. Treat the result as indicative and verify current rules independently.

Not included unless explicitly requested: personal circumstances not entered, provider discretion, future rule changes, professional fees and case-specific exceptions. Read the full calculator methodology.

Primary sources and official verification

Use these official sources to verify current rules before acting. Coverage and dates can differ across England, Scotland, Wales and Northern Ireland.

See the sitewide source policy.

How it works

Bi-weekly = 26 half-payments a year = 13 full monthly payments instead of 12. The extra payment goes straight to principal, accelerating payoff. The closer to the start of the term you do it, the more you save.

Worked example

£220k at 4.5% over 25 years: monthly £1,223 (£366,855 total). Switching to bi-weekly: paid off in ~21.4 years, saves ~£36,000 interest.

Who should use this

•Borrowers paid fortnightly
•Anyone wanting to clear the mortgage before retirement
•Comparing overpayment strategies

Common mistakes

×Not checking the overpayment cap (usually 10%/yr) — overshoot can trigger ERCs
×Assuming the lender will accept fortnightly billing — most won't, but a monthly overpayment achieves the same

Frequently asked questions

Can UK lenders take bi-weekly payments?▾

Most can't directly. The simple workaround: set up a standing order for 1/12 of your monthly payment as a regular overpayment.

Will I be charged?▾

Most lenders allow 10% overpayment per year penalty-free during a fixed deal. The 8.3% bi-weekly equivalent stays inside that.

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Mortgage Repayment →Mortgage Payoff →Mortgage with Extra Payments →