IRS officials are charged with enforcing the law's individual mandate, collecting new tax revenue and distributing subsidies to eligible participants in the new health insurance exchanges.
The House Oversight and Government Reform Committee, which will host Ingram on Wednesday, noted in a memo that the IRS is responsible for "at least 47 new provisions under ObamaCare."
The memo announcing Ingram's visit also said that the agency will play a role in the federal data hub, another source of concern for ObamaCare critics.
The House voted 235-185 in August to block the IRS from enforcing any part of the healthcare law. The move, if enacted, would effectively shut down the law's implementation.
—This post was changed to reflect that Ingram was in charge of tax-exempt organizations at the IRS between 2009 and 2010.