Step-Up in Basis
Also called: stepped-up basis, basis step up at death
A step-up in basis resets an inherited asset's cost basis to its value at the owner's death, erasing every unrealised capital gain accumulated during their lifetime. An heir can sell immediately and owe nothing. It's the reason 'buy, borrow, die' is a coherent strategy for the very wealthy, and the single most consequential provision in the US capital gains system — repeatedly proposed for repeal and never repealed.