One of the very first tasks you will encounter when entering information into Aplos or any fund accounting software involves determining your accounting year or “tax year”. (Within Aplos, System Preferences allows you to enter the appropriate information.)
An accounting year is simply the 12 month period over which an organization’s accounts are calculated. Deciding what 12 month period you use depends a great deal on what makes the most sense for your organization.
Calendar year – A calendar tax year is 12 consecutive months beginning January 1 and ending December 31.
Fiscal year – A fiscal tax year is 12 consecutive months ending on the last day of any month except December. A 52-53-week tax year is a fiscal tax year that varies from 52 to 53 weeks but does not have to end on the last day of a month.
For more in depth information, take a look at the IRS Publication 538.