For Stock Transactions TurboTax limits you to 7 digits to the left of the decimal point therefore you cannot enter a number 10 million or greater. To fix this you have to break it up to smaller numbers less than 10 million. However I just discovered a new TurboTax bug. For Total Proceeds and Total Cost Basis it limits you to 9 digits to the left of the decimal point. Therefore when it adds all the Transactions up if the Total Proceeds or Total Cost Basis adds up to 1 Billion or more then the TurboTax calculations go wacko and say you owe some ridiculous amount of Tax. For Example my Total Cost Basis was just under 1 Billion and Turbo Tax showed I owed 369K Tax which was correct. When I added 1 more stock entry which sent the Total Cost Basis over 1 Billion then the Turbo Tax couldn't handle it correctly and said I now owe 4.4 Million in Tax. I only had $5,188 Gain on that transaction so Turbo Tax should have said my Tax owed now is 374K. Instead of going from 369K to 374K Tax owed it jumped to 4.4 Million. On 1 of the TurboTax forms it shows Cost Basis Total 999,999,999.99. If I add 1 more entry that pushes Total Proceeds over 1 Billion then it will show Total Proceeds 999,999,999.99 and at the bottom of the page in small print it says Gross Proceeds - The amounts are too large. Some computed results are incorrect. My Account is under 5 Million but if you trade a lot like I do at the end of the year the Total Proceeds and Total Cost Basis can show huge numbers over 1 Billion. Has anyone else run into this 1 Billion Limit for the Totals which throws the TurboTax calculations way off into some other universe??? How do you get around this TurboTax Bug?

As for SoesWasBetter I assume his comment is just a smart aleck comment. He's evidently not a day trader or he would understand how the Total Proceeds and Total Cost Basis numbers can get very large by flipping over and over every day. For Example my friend who has an Account Value of 500K and Day Trades has Total Proceeds and Total Cost Basis numbers over 137 Million. That doesn't mean he has 137 Million Dollars. His Account is only 500K. It's just the way the math works out from Day Trade flipping day after day all year. If SoesWasBetter is serious then tell me what version of TurboTax you use that you claim works. I've already tested my Premier version and the Total Proceeds and Total Cost Basis values get stuck at 999,999,999.99 and cannot go higher and the Turbo Tax calculations break down when you hit those limits. It's not hard for a Day Trader to hit those limits if he's trading everyday in and out everyday and has an Account of 3 Million or more. As for Jack1960 I am putting the data into a spreadsheet and changing the numbers to smaller numbers but come out with the same Gain in the end. I assume that's all that matters is you report the correct Gain. I don't think it should matter what numbers you do the math on to get that Gain as long as it is the correct Gain. If I enter the real numbers manually as you might be suggesting Jack. TurboTax does not let me enter numbers that big manually. Maybe you can tell me more about what you are suggesting.

Dumping TurboTax seems to be a legitimate option. I did that many years ago for a similar problem. Whoever designed that software must not know about the "decimal" type. Ridiculous.

Do one line on Turbo Tax With total gross proceeds and cost... instead of e-file, print and mail in your forms along with the complete 8949.

andyf: How did you resolve your above matter, e.g., total proceeds/total cost basis over a billion? I have just run into the same issue this year for the first time. Did you still use Turbo Tax for that tax year?