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How to Calculate Mortgage vs Invest

What is Mortgage vs Invest?

When you have surplus cash, you can overpay your mortgage (guaranteed return at your rate) or invest it (potentially higher but uncertain returns).

Step-by-Step Guide

  1. 1Mortgage saving = Extra payment x mortgage rate (compounded)
  2. 2Investment return = Extra payment invested at market rate
  3. 3If investment return > mortgage rate: investing wins mathematically

Worked Examples

Input
500 GBP/month extra, 5% mortgage, 8% investment return, 10 years
Result
Overpay saves approx 78K GBP interest; investing grows to approx 89K GBP

Frequently Asked Questions

What is Mortgage Vs Invest?

When you have surplus cash, you can overpay your mortgage (guaranteed return at your rate) or invest it (potentially higher but uncertain returns). Use this calculator for accurate, instant results.

How accurate is the Mortgage Vs Invest calculator?

The calculator uses the standard published formula for mortgage vs invest. Results are accurate to the precision of the inputs you provide. For financial, medical, or legal decisions, always verify with a qualified professional.

What units does the Mortgage Vs Invest calculator use?

This calculator works with inches, watts. You can enter values in the units shown — the calculator handles all conversions internally.

What formula does the Mortgage Vs Invest calculator use?

The core formula is: Mortgage saving = Extra payment x mortgage rate (compounded). Each step in the calculation is shown so you can verify the result manually.

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