How can I ensure all my Capital Gains information shows up under Form 8949, and not on 1099-B (Schedule D, Part 1, 1a)?

Rswl11,

Your message title was confusing, talking about Schedule D, Part 1, 1a, when the body of the posting talked about 8, 8a.  In any event, I take it that you imported 1099-B information from Janus funds and they reported it to TurboTax as a summary rather than a sequence of individual long-term trades.  As you most likely realize, that is allowable so long as the set of transactions was clean, i.e. had no wash sales or other adjustments, as allowed on pages 2-3 of the Form 8949 instructions (https://www.irs.gov/pub/irs-pdf/i8949.pdf). 

One workaround I can suggest to force every Janus capital gains transaction onto Form 8949 is to delete the Janus funds entries and put them in manually.  This is, of course, only a cosmetic change that does not change the income and tax, but as one who does manually list everything on Form 8949, I can appreciate the aesthetic.

I played around with TurboTax to see if manually reporting multiple individual clean sales triggers an entry in Schedule D, line 8a.  It didn't, which strongly supports that Janus only transmitted the summary and not individual entries.  However, if TurboTax is actually showing individual Janus entries but somehow TurboTax was coerced into transferring their totals to Schedule D, 8a, rather than deleting and reentering manually, you could try modifying two of the entries to say that their reported basis was incorrect (code B) or an adjustment was needed for some other reason (code O) and adjust one up by a dollar and the other down by a dollar.  This would prevent the Janus items from satisfying the summary reporting exception and force them onto Form 8949 while not changing the income and tax on your return.

Let me know what you decide to do, if anything.  Inquiring minds want to know:-)