The lawmakers urged the Center for Medicare and Medicaid Services (CMS) to change the way it calculated the 2.2 percent cut.
The CMS assumed a 27 percent cut in Medicare's payments to doctors will take effect next year, as scheduled. But Congress almost always blocks those cuts from taking place and is likely to do so again.
The lawmakers want the agency to assume another temporary fix preventing the cut to doctors from happening. That would also lead the agency to scale back its proposed cuts to Medicare Advantage, which are Medicare plans administered by private insurance companies.
The CMS has said it has to base its projections on the letter of the law, and the letter of the law calls for a 27 percent cut in doctors' payments.
A new report from the Congressional Research Service, though, suggests that the CMS has the authority to assume another "doc fix" when calculating its Medicare Advantage payments.
The agency's current interpretation is well within its legal authority, the CRS said, but the agency could probably also justify changing its mind.