Generally, capital gains tax would be due. As to how much, it depends
on who was living in the house and when.
Assuming that the mother was living in the house when she died and the
house passed into her estate, then (a) the estate would have included
the value of the house in its estate tax return and (b) when the house
was sold by the estate of the mother's heirs, the basis for the house
would have been its value at the time of the mother's death, not the
original purchase price.
So:
Mother purchases house for $100M in 1980
Mother dies in 2004. House valued at $300M
Estate sells house in 2005 for $350M
The capital gain, subject to tax, would be $50M ($350M minus $300M)
If the house was the principal residence of your wife or her sister,
there may be an exclusion (partial or otherwise) from the capital
gains tax. |