Useful next calculations
When to use this calculator
- Before choosing between saving, investing or changing a contribution.
- When you want to compare cautious, base and optimistic return assumptions.
- When you need a projection before making a longer-term decision.
- When you want to see whether starting earlier or contributing more changes the outcome more.
A worked example
These are the example figures the calculator opens with.
| Input | Value |
|---|---|
| Profit (£) | £20,000 |
| Total Investment (£) | £200,000 |
For those figures the calculator returns:
- Return on investment: 10.00%
How to read your results
Return on Investment
A projected outcome under the growth rate you entered. Real-world returns fluctuate, so also check a more conservative assumption.
Method & assumptions
This calculator divides net profit by total investment and expresses the result as a percentage. It is a simple, universal performance measure that works across all property strategies: buy-to-let, flipping, development, and commercial property. The key to an accurate result is using comprehensive figures for both inputs.
For profit, start with sale proceeds or current market value, then deduct purchase price, all transaction costs (property transfer tax, legal fees, surveys), any renovation or improvement spend, ongoing costs during the holding period, and selling costs including estate agent fees. For investment, use the total cash outlay — deposit, fees, and capital improvements — rather than the gross property price if you used mortgage finance. Note that this calculator does not model Capital Gains Tax, which is chargeable on disposal of investment property at 18% (basic rate) or 24% (higher rate) after your annual CGT allowance. Always seek professional tax advice before completing a property transaction.
Common mistakes
- Assuming a constant return without checking a more conservative growth rate.
- Forgetting ongoing contributions, fees or tax wrappers where relevant.
- Focusing only on the final balance instead of the path required to reach it.
- Ignoring the drag of charges over a long period.
What to do next
- Test a cautious, expected and optimistic growth rate.
- Compare this result with related savings or retirement tools before committing more money.
- Consider charges and any tax wrapper that applies.
- If the projected balance falls short, increase the contribution until the result meets your goal.