U.S. tax collectors will be responsible for several major provisions of the Affordable Care Act, including the individual mandate to buy health insurance and tax credits for small businesses and low-income individuals.
The IRS has estimated that it will need more than 2,000 full-time employees devoted to these functions by the end of the year, though some have called that figure optimistic.
On Thursday, Boustany also asked the IRS to reveal how much money it has received from the Health and Human Services (HHS) Department for implementation since 2010.
Republicans in Congress have raised objections to these transfers, saying they open the door to misuse of taxpayer dollars.
Boustany recently charged the IRS with "a significant amount of waste" in its operations.
The administration released its proposed rule for collecting the healthcare law's tax on health insurers earlier this month.