Can I e-file my return even though I have to send the IRS support for my short and long term gains that are classified as "transactions for non-covered lots"

[CapB · Accepted solution]

Yes, you can still e-file even if you are required to mail Form 8453 and Form 8949 to the IRS.

IRS regulations require mailing Form 8453 (U.S. Individual Income Tax Transmittal for an IRS e-file Return), Form 8949 (Sales and Other Dispositions of Capital Assets) with other supporting documentation, when e-filing and using summary reporting methods to record large quantities of stock transactions.

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