>>76421202Legally, it must be reported but in general the bulk of people donating plasma have less income than the standard deduction for federal taxes. Some states like Ohio exempt blood and plasma donations from taxation. At that level, the IRS is unlikely to bother, even if you do go over the standard deduction.
There's also the issue of eligibility for food stamps, Medicaid, and other benefits programs. Food stamps in particular sees plasma as unearned income. Depending on the state, they can be very aggressive about going after you if you don't report your income from selling plasma. In general, for every three dollars you get from plasma sales, your food stamps are reduced by one dollar. If you don't report it and they find out about it, not only can they require you to pay it back, they can kick you out of the food stamp program, usually for three years.