If you chose to report your transactions using the summary method, then you will have to mail follow up documents.
The rest of the answer below is going to assume that you choose to use the summary transaction method of reporting your 1099B transactions instead of entering individual sales.
Short Answer: You do not really need to mail Form 8949, but you do need to mail your supporting statements, such as your brokerage statements (Form 1099B) and Form 8453.
When you use this summary method of reporting (i.e. you just entered your totals and not each individual transaction), in some cases, the IRS still wants the supporting details sent to them.
Note: In limited situations, you’re allowed to summarize investment sales without providing complete details. If you are summarizing multiple investment sales that are either Box A sales or Box D sales, and there are no adjustments necessary (i.e. Code W for wash sales), then it is not necessary to mail in a statement with further details. Turbotax will tell you this when your sales meet the criteria and will not prompt you to mail any statements.
So, if you are being prompted to mail further statements, Form 8453 says to attach Form 8949, Sales and Other Dispositions of Capital Assets (or a statement with the same information), if you elect not to report your transactions electronically on Form 8949.
When you use the summary method, TurboTax only produces a Form 8949 with the summary totals that you entered, not the individual transactions, so the Form 8949 that is included in your return is NOT sufficient for this purpose. (Though, you can include it with the mailing as a reference)
You need to use Form 8453 to mail the brokerage statements that show the details of your transactions. Statements should include the following items for each transaction (these are usually reported on your Form 1099-Bs:(
- Description
- Date acquired,
- Date sold,
- Sales price,
- Cost basis,
- Gain or loss for each sale,
- Sale category based on how the sale was reported to you and the IRS, and
- In some cases, there will be an adjustment code and adjustment amount.
NOTE: As discussed above, any sales summaries that include only Box A or Box D sales, and which have no adjustments to gain/loss, do not need to be included on a statement mailed to the IRS.
If you are e-filing your tax return, then mail your statements along with Form 8453 to:
Internal Revenue Service
Attn: Shipping and Receiving, 0254
Receipt and Control Branch
Austin, TX 73344-0254
If you need a blank Form 8453, you can download this pdf, enter your address information and check the box for Form 8949 (this form is really just a cover sheet).
