TurboTax Online is equipped to handle around 500 individual transactions (give or take) per brokerage account before the performance starts to deteriorate.
If you need to enter a bunch of stock transactions with a total sales volume of less than $10,000,000 (ten million), you can enter a summary for each sales category.
Another alternative is to switch to the TurboTax CD/Download software which handles around 2,000 individual transactions per brokerage.
How to enter a summary in lieu of individual transactions
Your brokerage statements should include a summary of your transactions, grouped by sales category, for example, "Box A short-term covered" or "Box D long-term covered". You'll enter the summary info instead of each individual transaction.
- Open your return (if it's not already open) and search inside TurboTax for the phrase stock sales.
- Select the Jump to link in the search results.
- Answer Yes to both Did you sell any investments? and Did you get a 1099-B?
- If you land on Here's the investment sales info we have so far, select Add More Sales. Then answer Yes to Did you get a 1099-B?
- When asked how you want to enter your 1099-B, select I'll type it in myself.
- Select or enter your brokerage on the next screen and continue.
- On the following screen (Tell us about...) select the second option, I'll enter a summary.
- On the same screen, you'll now be able to enter the total proceeds (sales) and cost basis, along with the sales category. Refer to your 1099-B for the amounts and category. When finished, select Done.
- Follow the onscreen instructions to enter additional sales or to view a summary.
When you are done entering all your sales transactions, you'll eventually come to the Here's the investment sales info we have so far screen where you can edit, delete, or enter more sales.