Legal, professionally installed tint
Generally not a declarable modification. It does not change the vehicle's performance, value or risk profile in a way carriers are concerned with, and it is common enough to be unremarkable.
Check your policy wording anyway — some policies define modifications broadly enough to want anything non-factory disclosed. It costs a phone call.
Illegal tint is a different question
If your front windows are below the legal limit and you are in an accident, an insurer has grounds to argue the vehicle was not in a legal condition. Whether that argument succeeds varies, but it is an argument you have handed them for no benefit.
It also cannot help in a liability dispute where visibility is at issue. Keep the front doors legal — the comfort you actually want comes from ceramic film, not from darkness.
What tint does not do
It does not raise your premium. It does not affect a glass claim on a rear window that happens to be tinted.
It is worth knowing that a comprehensive glass claim replaces the glass, not the film on it. If a tinted rear window is replaced, re-tinting that pane is normally your cost — worth budgeting for if it happens.
Need this done rather than explained? There is no shop to drive to. We come to wherever your car already is — your driveway, your workplace car park, an apartment lot, or the side of the road it stopped on — anywhere in greater Sacramento, with no call-out fee and no mileage charge. Give us the year, make and model and you will have a firm price before the call ends.