Entered my charitable deduction but my taxes didn't go down and I am itemizing

[Sandwisch]

Hi,

I am itemizing my deductions using Schedule A.  I am not doing the standard deduction as my itemized deductions are more.  I entered a charitable donation of $40 under personal deductions and credits.  It shows up on Schedule A and my total itemized deductions increased by $40.  However the tax I owe did not go down.  Why?

For fun I tried $41, $42 and $43 for the donation.  When I enter $43 my taxes owed goes down by $11.  If I enter $42 or below, my taxes don't change.  This does not make sense to me.  Shouldn't any increase in my itemized deductions total on Schedule A result in some tax going down no matter how small an increase?

I would think my $40 would reduce my taxes by about $10 but it doesn't.

[JulieS]

Yes, that's logical, but if you check the tax tables they go in $50 increments once you get above $3,000 so any deduction less than $50 may not change your tax. See the tax tables here.