For most players, you are looking at around 8% in New York State.
It’s hard to precisely say what it is, because it all comes down to the exact incomes.
However last year, the state income tax ranged from 4% to 8.82%. The Average player like ranges in the 7-8% range.
In Vegas, Tampa, Arizona (I think), Sunrise, Dallas (I think) there is no state tax. So their dollars go 7-8% farther than that of the New York State teams.
However you have to factor in that players pay state taxes on where the games are played. Meaning, out of 41 road games, let’s say 30-35 are in state income tax places.
So now, those players are still paying a bit of state income tax on 30-35% of their pay cheque.
So the real advantage comes if a team like Vegas does heavy signing bonuses.
Now this was a while ago, but I believe someone went through everything from state taxes to federal taxes average cost of living and such, and to match Tampa Bay’s 8.5M contract, Toronto would’ve had to offer 9.8-10.3M IIRC