Having just gone through this, and spending a fair amount of time on it, I understand the issue of what original poster was asking and some of the interim postings misunderstanding what is being described and asked.
If you have many, many brokerage transactions - in the thousands (with commission free trading and brokerages providing program interfaces to their systems these days, it is quite doable), you must still report the entirety of what is contained in the 1099-B statements. Turbotax (Premium) actually choked and locked up when importing from my brokerages because it could not handle the number of transactions. For these folks, there are a couple of options:
1. Utilize summary entries. Within Turbotax, there is a help topic titled "Should I summarize my sales". Basically, any transactions identified as Box A or D can be netted together and provided as a single entry for each category. However, transactions with any adjustments (W wash sale, for example), or any which are cost basis not reported to IRS still must be individually entered. Here's the meat of what the Turbotax help topic provides:
"Here's a tip that might help: you can report individual sales as well as summaries for the same account. So let's say you have an actively traded account with 500 stock sales that are all Box A or Box D sales. Only 3 of the sales require any adjustments. In this case, you can report the 3 sales that require adjustments individually. Then you can report all the remaining sales by entering two sales summaries. By entering just 5 sales you've covered all 500 sales and don't need to mail in any additional info."
2. If you still have many, many individual entries that would need to be manually entered, just provide all transactions summarized and category netted, and mail in "a statement". The statement does not have to be the 1099-B, it can be one that you create in a spreadsheet (for example) providing the necessary transaction information - maybe your brokerage provides a simple CSV that can be imported to a spreadsheet and edited down to just the relevant transactions and information. However, again, in the case where the taxpayer has a huge amount of transactions and the brokerage only provides the 1099-B (printout or PDF), that may be the "statement" you mail in.
@ross in ss- it applies whether you mail in your return or you file electronically. If you mail in, you provide the "statement" with your mailed in return. If you file electronically, you mail to Austin TX. This is all provided within/by Turbotax if/when you choose to make summary entries.
Now, my question - you've thrown your hands up, decided to no longer waste hours individually entering the individual adjustment transactions, used summary entries, got everything e-filed/accepted and mail the statement with 8453 to Austin TX...is there an equivalent process to follow for the state tax return? Turbotax did not say anything about that. However, knowing my state and that they always want the Federal 1040, I can see myself getting a nasty letter from my state revenue servicing center in time requesting it. I've googled and thus far come up empty-handed. I'm thinking I'll just have to wait and see.
There is another thread on this topic:
https://ttlc.intuit.com/community/taxes/discussion/turbo-tax-says-i-must-mail-form-8453-8453-wants-m...
It seems that there was confusion around this in the past, and I believe that there have been updates to the software that made things clearer based on some suggestions of the posts in the above thread - Turbotax guided me through what needed to be done. This was the first year I had to do this, and it was not terrible.
I do agree with others who mention it - IRS already has the entirety of the 1099-B, so mailing it, or equivalent information contained in it seems to be redundant.
