WayliMortgage & Investing

Mortgage & Investing

Should I overpay my mortgage or invest?

Compare the certain reduction in mortgage interest from overpaying with the possible future value of investing the same spare cash.

For
People with spare money choosing between mortgage overpayments and investing.
This page helps you
Understand the evidence, assumptions and trade-offs needed to compare the two paths.

Quick answer

Overpaying gives you a certain reduction in mortgage interest based on the figures entered. Investing could produce a higher value, but the return cannot be known in advance and is not guaranteed. The Mortgage Decision Engine compares both paths using the same amount of spare money over the same period.

Worked example

What the same £200 a month could change

On a £180,000 mortgage at 4%, with 25 years remaining and a £950 monthly payment, overpaying could avoid £30,159 of mortgage interest and clear the mortgage about 6.6 years sooner.

The mortgage effect is calculated from the entered terms. The investment result is a projection based on an assumed return, not a recommendation or guarantee.

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Canonical worked example

On these assumptions, investing has a projected value £48,427 higher than overpaying first.

This is a modelled comparison, not a recommendation. Investment outcomes are projections and are not guaranteed.

How the mortgage paths differ

Calculated mortgage effects from the figures entered.

Normal mortgage
September 2051
With overpayment
February 2045
79 months earlier£30,159 interest avoided

Illustrative relationship; dates are calculated from the entered terms.

See how the balance changes

A few checkpoints from the same mortgage calculation.

Now£180,000shared starting balance
After 1 year
Normal£175,722
Overpayment£173,278
After 13 years
Normal£108,540
Overpayment£67,705
After 26 years
Normal£0
Overpayment£0
Overpayment payoffFebruary 2045
Normal payoffSeptember 2051

Calculated from the entered balance, rate, normal payment and overpayment.

How the paths meet at the horizon

Overpay spare cash£200 each month
Mortgage clears earlierFebruary 2045
Released cashflow becomes available£1,150 each month
Invest through the shared horizon£115,628 projected value

Both paths are compared at the same 301-month horizon.

What the investment path builds

£61,095contributed
£102,959projected growth
£164,055projected value at the common horizon

Based on the assumed 7% annual return.

What moves the model?
Mortgage ratemortgage effect
Investment returnprojected growth
Remaining termcomparison horizon
Spare cashboth paths
Lender rules / early repayment chargespractical constraints

These are the main assumptions to check, not another scenario builder.

Personalise the worked example

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Change the figures that matter to this question. Your answer stays here and uses the same Mortgage engine.

One supporting explanation is available after the comparison.

Why mortgage-free sooner may not mean more money

Educational comparison only. Returns are not guaranteed. This is not personalised financial advice; check your mortgage terms and early repayment charges.