After I efiled my return TurboTax presented me with a message that I must print out and mail Form 8453 to the IRS, with Form 8949 attached, but only if I elected "not to report your transactions electronically on Form 8949". When I look at the forms in my return I see a completed Form 8949. Was this form filed with my electronic filing? And if it was do I still need to mail Form 8453 to the IRS? (And if form 8949 was electronically submitted with my efile, why was I not presented with the option to elect "not to report [my] transactions electronically" when inputting information off of my brokerage statement?)
If you entered category totals for the transactions on your Form 1099-B then you need to mail Form 8483 with a copy of your 1099-B. If you entered transactions one at a time, the you don't need to mail Form 8453. If you only reported sales summaries that included only Box A or Box D sales, and which had no adjustments to gain/loss (e.g. wash sales), you do not need to mail a statement to the IRS.