  We estimate, in a large class of scenarios, the sensitivity to new physics in
B_d and B_s mixings achievable with 50 ab-1 of Belle II and 50 fb-1 of LHCb
data. We find that current limits on new physics contributions in both B_{d,s}
systems can be improved by a factor of ~5 for all values of the CP violating
phases, corresponding to over a factor of 2 increase in the scale of new
physics probed. Assuming the same suppressions by CKM matrix elements as those
of the standard model box diagrams, the scale probed will be about 20 TeV for
tree-level new physics contributions, and about 2 TeV for new physics arising
at one-loop. We also explore the future sensitivity to new physics in K mixing.
Implications for generic new physics and for various specific scenarios, such
as minimal flavor violation, light third-generation dominated flavor violation,
or U(2) flavor models are studied.
