The end of the year is coming up, and that usually means giving money to a meaningful cause, donating old clothing, or volunteering for our favorite charity. Along with the joy giving back brings us, there’s also a powerful financial motivator: the ability to lower your income tax bill with tax deductible donations! But before you dash off on a charitable streak, there are 5 important rules to remember to make sure what you’re giving qualifies as a tax deductible donation.

But first — how do you figure out the value of your tax deductible donations? It all comes down to your tax rate and tax bracket. Here’s a simple calculation you can use to find out:

As a back of the envelope calculation, the formula is: [Your marginal federal tax rate (25-39.60%) + your state tax rate (0-13%)] x the value of your donation = The value of your tax deduction 

For example, if your combined tax rate is, say, 35% and you donate $1,000 to charity, you pay $350 less in taxes. Clearly the government wants us to give!

Now for those 5 rules to remember for your tax deductible donations:

1. Unfortunately, you can’t write off volunteering time. As generous as giving your time is, you can’t quantify it, and therefore it can’t be written off. But, for example, if you’re using your car for something related to volunteering, you may be able to write off some of the mileage. For more information, visit (here’s a helpful summary).
2. Make sure the organization you are donating to is an IRS-qualified charity. Usually they will state their status on a receipt for your donation. You can check out their status on the IRS website.
3. If you give cash to charity, you must be able to itemize your deductions. Pull out last year’s tax return and check to see if you normally itemize, or if you take what’s called the “standard deduction.” This may not change your decision to give, but it will tell if you get an extra tax break from your cash donations. For those of us giving a lot to charity: You can’t donate more than 50% of your adjusted income in any given year. Learn more from the IRS to find out more. One caveat: If tax laws do change in 2018, you may no longer be able to itemize your deductions.  This is due to state tax deductions, mortgage interest deduction, etc. which may actually hurt your ability to write off your donations to charity.
4. You can donate old clothing, furniture and items that have value (they should be in reasonable and reusable condition). But remember, you can only deduct the fair market value of what someone would pay for these items. So be honest about that well-loved pair of loafers! If the value of what you donate is over $500, you need to fill out a special form.
5. For more valuable contributions like artwork, be aware that there are special rules that dictate how much you can donate and how to value them. Be sure to consult a professional appraiser before doing so.

If you’re thinking of giving to charity, act now! In order to count for this year’s tax return, you have to complete your donations by December 31st. As always, consult with a tax professional or financial advisor to better understand your particular situation — but most of all don’t lose sight of the joy in giving!