Co-ownership Property Calculator
Calculate how to split a property purchase between two buyers with different initial capital contributions. Get each person's ownership share, mortgage split, and monthly costs.
Property Purchase Price
Closing costs (~3–4%): title insurance, escrow, recording fees, lender fees.
Person A
Person B
Mortgage
Independent Split
Mortgage and running costs split is independent from the ownership share. Adjust freely based on income or agreement between parties.
Monthly Running Costs
Ownership Share
Total Acquisition Cost
Mortgage Split
Monthly Cost Split
Exit Simulation (Buyout)
Amount each person would pay to take full ownership (at purchase price, assuming 3% annual appreciation).
Estimated Net Worth (3% annual appreciation)
| Year | Property Value | Person A | Person B |
|---|---|---|---|
| 10 | $537,567 | $178,415 | $70,902 |
| 20 | $722,444 | $13,748 | $0 |
| 30 | $970,905 | $0 | $0 |
How It Works
Ownership share is proportional to each person's capital contribution relative to the total equity (purchase price + acquisition costs − mortgage). The mortgage split and monthly running costs split are independent from the ownership share — you can set them freely (e.g. 50/50 even if ownership is 60/40). Use the "= Share" button to copy the ownership percentages to the cost splits if you want them aligned.
Frequently Asked Questions
How is the ownership share calculated?
Ownership share = each person's capital contribution ÷ total equity (down payment). If Person A contributes €60,000 and Person B contributes €40,000, Person A owns 60% and Person B owns 40%. The mortgage and running costs can be split differently — for example 50/50 if both have equal incomes, regardless of the ownership percentage.
What happens if one person wants to sell their share?
In most jurisdictions, a co-owner can sell their share or force a sale (partition). A co-ownership agreement (tenancy in common in UK/US, indivision in France, pro-indiviso in Spain) should specify the right of first refusal, valuation method, and exit conditions.
Should we use joint tenancy or tenancy in common?
Joint tenancy means equal shares and automatic inheritance to the survivor. Tenancy in common (or equivalent) allows unequal shares and independent inheritance. For unequal contributions, tenancy in common is almost always the right choice.