QuickBooks Mac 2016 does support Sierra.  Be sure to run QuickBooks->Check For Updates after you update the OS (maybe before, too, just to be thorough).

Resolution for 'be available issue: 'OS Sierra final was released today. Does QB for Mac 2016 support the new OS? If not, when will a desktop version of QB for Mac be available that will run on OS Sierra?' available: Yes.

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