This messaging is confusing:

[LBFam]

From Form 8453

[X] 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.

This is checked on required forms, but I did not elect, knowingly to no send my Form 8949 electronically?  IE turbotax should have sent my form 8949 electronically, correct?  So, sending 8453 and 8949 through snail mail should not be required, correct?  If so, seems like a bug.

The reason for this appears to be because I received a 1099-B w/out cost basis and corrected the cost basis.  It was for a pair of transactions totalling 98 cents so not materially affecting my overall taxes.

Due to the immaterial affect on the taxes, the having received a 1099-B, and filing the 8949 electronically, I should not need to mail the 8453, correct?

[MaryK4]

If the 1099-B shows basis was reported to the IRS and you made an adjustments in box 1f or 1g, you are required to mail in the explanation.  TurboTax automatically adds the Form 8453 if you meet one of the requirements to send it. (it does not have to be an affirmative election on your part). See E-file.

You should mail the 8453 with the explanation to avoid future IRS issues.

[LBFam]

I had to mark the basis as adjusted because it was missing on the 1099-B.  The basis was not reported to the IRS at all.  The values were in the short term section, not reported to the IRS.

The confusing thing about the message is that the message says "if the 8949 was not sent electronically".  My question is, was my 8949 sent electronically?  Which would mean I don't have to mail it?

[JotikaT2]

No, Form 8949 is not sent electronically. It does need to be mailed in along with the selected information as indicated on the form and sent to the IRS.

Do I need to fill out or mail in Form 8949?

[baldietax]

Presumably you made the adjustment on a sales summary, which will trigger the need to send the statement.

Instead if you input any item(s) with adjustments on a separate 1099-B in TT as "one by one" with the detail then TT should generate 8949 and send that electronically; and then you should reduce your sales summary by the corresponding amounts, so your Schedule D is whole.  No mailing of your statement and form 8453 should be needed.