Sell Shares to Buy a House vs Keep Calculator

This calculator helps you decide whether to sell shares to put a bigger deposit on a house, or to keep the shares and borrow more on the mortgage instead, a choice many investors face when buying a home in New Zealand. The trade-off is really about two rates pulling against each other. If you keep the shares, you expect them to grow, but you carry a larger mortgage and pay more interest. If you sell them, you borrow less and save that interest, but you give up the growth the shares might have delivered. Which wins depends on whether your expected share return is higher or lower than your mortgage rate. You enter the value of the shares in question, the annual return you expect from them, your mortgage interest rate, and the number of years over which to compare. The calculator works out the growth you would expect by keeping the shares, the extra mortgage interest you would pay by borrowing that amount rather than using the shares, and the net difference, pointing to the option that leaves you better off. Bear in mind it ignores tax, the real volatility of share markets, and that mortgage interest is paid from after-tax income, so treat it as a guide for thinking it through rather than a precise answer. Estimates only, not financial advice.

Ignores tax, share market volatility, and that interest is paid with after-tax money. Share returns are not guaranteed. Estimate only, not financial advice.