Sometimes. It depends on the amount of the donation. While prudence would have you obtain a receipt every time you make a cash donation, this isn’t always practical or even possible.
When you place cash in a collection bucket outside a store during the holidays, it’s hardly practical or even possible to obtain a receipt. The same is true if you donate cash at church, or if you donate at traffic stops organized by a charitable organization.
In these cases, as long as the donation is under $250, simply note the date, the amount, and the name of the organization that you donated to.
However, whenever it’s practically possible, obtain a receipt even for amounts under $250 because the paper trail may come in handy if the IRS ever questions your deduction.
If you donate $250 or more at one time to one charitable organization, you must obtain a receipt in order to take this donation as a tax deduction. The IRS requires it.