If you have a TTS/trading entity, and have elected mark-to-market treatment, does interest income (such as treasury coupon payments, or interest paid when treasuries mature) pass through to the entity owners as interest, or does it get lumped in with tradings gains and reported as part of the lump sum on form 4797? Same question for dividends. The reason I ask: if it DOES get passed through as interest, I will continue using tbills as my "cash" holding, since there is no state tax. If it does NOT get passed through, and instead simply gets added to 4797 gains, there is no tax benefit, so I would just use my broker's money market sweep feature. The money market is in govt repo securities with the same yield, but it gets paid out as ordinary dividends rather than treasury interest. Easier in that I don't have to roll at maturity, but taxed higher.