My 1099-B has a $ amount for cash received and a $ amount from stock received in a merger. Must I report both

For the cash, yes. For the stock, no.





Other than having a fractional share that might cause you to declare some small income on Schedule D, there is generally no immediate tax consequence.





You report the stock when you sell it.|||Yes. You need to report what's on the 1099-B.





To the extent that you get cash from a merger, you get taxed on it.