Renting and investing the difference means investing the cash you would otherwise commit to buying, plus any monthly housing savings. The result depends on the rent, ownership costs, investment returns, and whether you actually make the contributions.
The strategy has two sources of investment money
First, invest the money a purchase would consume upfront: the down payment and buying fees. In our hypothetical €300,000 purchase, a 20% down payment and 6% buying costs total €78,000.
Second, invest the monthly difference whenever renting costs less than owning. The first month's total ownership cash outflow in the same example is €1,402.71, compared with €1,200 rent. That leaves €202.71 to invest.
Keep the budgets equal. Adding an extra monthly contribution to the renter while giving the buyer no equivalent money makes the result misleading. Our Home calculator gives both paths the same extra savings; the buyer uses them to repay the mortgage first, then invests them after the loan is cleared.
The monthly difference will change
A fixed mortgage payment can stay level while rent rises. Property tax, maintenance, and insurance may rise too. Once the loan is repaid, buying can have much lower cash outflow and the buyer can invest more.
The illustration does not assume renting stays cheaper forever. Each month, whichever option has lower housing costs invests the difference. This lets the buyer build a stock portfolio as well as home equity.
Real expenses are less regular than the model's monthly allowances. A major repair can temporarily absorb money you hoped to invest, while a rent increase can shrink the renter's contribution.
Try different investment returns
The table changes only the assumed stock return. Home and rent growth stay at 2%, annual investment fees at 0.3%, and sale costs at 3%. Both options sell their assets after ten years, with capital gains taxes set to zero for this illustration.
| Stock return before fees | Buy + stocks | Rent + stocks |
|---|---|---|
| 3% a year | €168,900 | €119,300 |
| 5% a year | €168,900 | €143,200 |
| 7% a year | €168,900 | €171,600 |
Buying wins in the first two scenarios; renting is ahead in the third. The buyer's result is unchanged here because this specific scenario has no spare money invested on the buying path during those ten years. That will not hold for every set of inputs.
These are steady-return scenarios. They do not show a market crash just before you need a deposit, periods of unemployment, or changes in tax rules. None of the chosen rates is a prediction.
All assumptions for this example
A hypothetical €300,000 home, €1,200 monthly rent, 20% down payment, a 3.5% fixed mortgage for 30 years, and buying costs of 6%. Annual property costs are 0.2% tax, 1% maintenance, and 0.1% insurance, calculated on the home's changing value. Home value and rent each grow 2% annually. Stocks return 5% before a 0.3% annual fee. No extra monthly savings. Capital gains taxes are set to zero to isolate the comparison; this is not a statement about local tax rules. The savings alternative uses 2% interest and zero interest tax.
These results include selling everything at the indicated year and a 3% home selling cost. Amounts are nominal, without inflation adjustment. Our calculator's headline result is after 30 years; earlier years appear in the chart. Rates are held constant, and actual returns, expenses, and tax treatment will differ.
Make the contributions realistic
Decide how much cash you need to keep accessible before allocating money to investments. A future home deposit needed on a fixed date has a different time horizon from money you can leave invested for decades. The SEC's asset allocation guidance connects time horizon with risk tolerance.
If you choose to invest, use a contribution amount you can maintain after irregular bills. A scheduled transfer can help, but it cannot create savings that the budget does not contain.
Review costs as well as the headline return. Investment fees reduce the amount that compounds, and tax can reduce what you keep when selling. Enter those rates in the comparison where relevant.
Know what the strategy does not solve
A growing investment portfolio does not provide permanent rights to a rented home. Buying can offer control and stability that matter independently of net worth. Renting can provide flexibility that you value even if a model favors buying.
The strategy also requires accepting investment risk without the routine of a mortgage payment forcing saving through principal repayments. Consider how you would react to a falling portfolio and whether you might spend the upfront cash instead.
Use the calculation to identify the tradeoff in your circumstances, then choose a budget and investment approach you can sustain.
Published by Rent vs Buy. Prepared with AI assistance, with primary sources linked in the text. Worked numbers are checked with automated tests against our calculator models or the stated formulas. Local fees and tax rules vary; these examples are not personalized advice.