Let's use your actual numbers in your original post.
I pay $250 and get $450 in credits to pay for meals each month.
So I assume that $250 you pay is paid from your taxable income. If it's not paid from taxable income, then you can stop here. You have nothing to claim or deduct.
Assuming the only thing you get for $250 is $450 in meal credits, that means 45 cents on the dollar for each credit. ($250 is 55% of $450) (If meal credits is just part of what you get for your $250, that changes the whole dynamics of this.)
I spend $300 in credits and have $150 unused.
So 55% of $150 is $82.50. Therefore, $82.50 would be the value of your donation.
If this is a monthly thing, then that's $82.50 times twelve, or $990 a year that you donate. Assuming the organization you donate to is q qualified charity, and assuming your donation is a qualified donation, I seriously doubt that $990 a year will have any impact on your tax liability. Remember, when it comes to your SCH A deductions, they don't kick in until the total of those deductions exceeds your standard deduction. When the standard deduction for tax year 2021 being set at $12,550 at present for a single person or someone who files married separate, You're not coming anywhere close.
Living in a retirement community tends to indicate you don't have a mortgage payment and don't pay property taxes on any real estate. So unless those assumptions are wrong (and I could be) I just don't see any way your itemized deductions would ever exceed your standard deduction based on the information provided, and the assumptions I am making.
