How do I calculate year-end IRA basis after doing a partial backdoor Roth conversion?
In 2015, I had 3 accounts: a rollover IRA, a traditional IRA, and a Roth IRA. On 12/31/2015, my rollover IRA had a balance of $50k. In early 2015, I did a backdoor Roth conversion of $5k, which still left my traditional IRA with no balance. However, of the $5k backdoor, I had to pay taxes on $4,545 of the conversion because I had a mix of taxed and untaxed money. I'm fine with all that. My question though, is what is my IRA basis at the end of 2015? TurboTax is telling me it's $4,545, but I don't understand why the amount is equal to the taxable amount of the conversion if that money has already been converted to a Roth. Also, if I made no contributions or withdrawals to any IRA's in 2016, what is my IRA basis at the end of 2016? Thanks.