Note the IRS language about nonprofit filing:
“Most small tax-exempt organizations whose annual gross receipts are normally $50,000 or less can satisfy their annual reporting requirement by electronically submitting Form 990-N if they choose not to file Form 990 or Form 990-EZ instead.”
The term “gross receipts” means all money received with no expenses. Regarding the “normally $50,000”,
“To determine whether an organization's gross receipts are normally $50,000 or less, apply the following test. An organization's gross receipts are considered normally to be $50,000 or less if the organization is:
1. Up to a year old and has received, or donors have pledged to give, $75,000 or less during its first tax year;
2. Between 1 and 3 years old and averaged $60,000 or less in gross receipts during each of its first 2 tax years; or
3. Three years old or more and averaged $50,000 or less in gross receipts for the immediately preceding 3 tax years (including the year for which the return would be filed).”
So, your organization may still file the 990-N, which is significantly easier than the 990EZ or the 990 if it falls within these three tests. The key is how the IRS defines “normally”. For older nonprofits, the average test may work out. For example, if the organization has $80,000 in income in 2015, but has $20,000 and $30,000 in prior years, averaging out #43,333, still below $50,000 -- you can still file the 990-N and do a happy dance!
See more here Measuring Program Success
Check out 'Nonprofit Finance: A Practical Guide"