1,200 small S.D. nonprofits risk IRS status

"It really is serious," said Sara Koslow, a spokeswoman with the National Council of Nonprofits. "They really will lose their tax-exempt status."

The IRS and other nonprofit advocacy groups have been trying to inform nonprofits about the issue, Koslow said. The IRS has sent out more than a million letters since the law was changed. But Koslow notes that many of the organizations are run by volunteers where there's high turnover, so the information might not have trickled down.