Here’s what the IRS says about written acknowledgements for charitable donations:

Taxpayers who make single donations of $250 or more to a charity must have one of the following:

• A separate acknowledgment from the organization for each donation of $250 or more.
• One acknowledgment from the organization listing the amount and date of each contribution of $250 or more.

The $250 threshold doesn’t mean a taxpayer adds up separate contributions of less than $250 throughout the year.  For example, if someone gave a $25 offering to their church each week, they don’t need an acknowledgement from the church, even though their contributions for the year are more than $250.

A taxpayer must get the acknowledgement on or before the earlier of these two dates:

• The date they file their return for the year in which they make the contribution.
• The due date, including extensions, for filing the return.

• If the acknowledgment doesn’t show the date of the contribution, the taxpayers must also have a bank record or receipt that does show the date.

You can read the full IRS Tax Tip about written acknowledgements here.