non-deductible existed before Roth IRA became the law. It still has some usefulness. Say this year you make 200K (not qualify for Roth)and you are at 25% tax bracket. You put 6K non-deductible IRA instead of deductible IRA and you overpay $1500 in tax. Two years later, you will be 33% tax bracket. You want to convert 6K to Roth IRA, not take your gain into account, your 6K is non taxable in conversion. If you would put 6K in deductible IRA this year, you would have to pay $1980 in tax. So overall you save $480 (1980-1500).
【在 P*******r 的大作中提到】 : non-deductible existed before Roth IRA became the law. It still has some : usefulness. : Say this year you make 200K (not qualify for Roth)and you are at 25% tax : bracket. You put 6K non-deductible IRA instead of deductible IRA and you : overpay $1500 in tax. Two years later, you will be 33% tax bracket. You want : to : convert 6K to Roth IRA, not take your gain into account, your 6K is non : taxable in conversion. If you would put 6K in deductible IRA this year, you : would have to pay $1980 in tax. So overall you save $480 (1980-1500).