An influential conservative think tank is calling for reducing the cost of troop housing allowances as part of the fiscal 2018 budget.

The Heritage Foundation, based in Washington, D.C., proposed reforming the Basic Allowance for Housing to more closely match actual spending as part of a report released Tuesday, called "Blueprint for Balance: A Federal Budget for Fiscal Year 2018." The blueprint provides guidance on how to curb the $20 trillion federal debt in part by eliminating the annual deficit.

"This allowance is designed to help service members pay for housing," the report states. "This is not military compensation. Housing allowances should be based on the amount of money that service members must pay to obtain adequate housing."

It continues, "Service members are not entitled to, nor should they have any expectation, that money above what they pay for housing can be retained as 'extra compensation.' "

Specifically, the document cited the potential value of previous, though so far unsuccessful, attempts by Congress to base BAH on proof of a lease or mortgage in the amount a service member spends on housing and consolidate allowances for married couples -- changes estimated to save $116 million in the fiscal year beginning Oct. 1.

The Senate last year tried to curb BAH for new entrants beginning in 2018 by covering only what they actually pay in rent or a mortgage and reducing the combined value of the benefit received by military couples or roommates. The idea was to make the military benefit -- which varies by paygrade, dependent status and region in the U.S. -- more like theOverseas Housing Allowance, which covers only housing expenses.

Fiercely opposed by military advocacy groups such as the Military Officers Association of America, the language wasn't included in the House of Representatives' defense bill and ultimately wasn't included in the compromise version of the legislation.

However, the 2017 National Defense Authorization Act, which sets policy and spending goals for the fiscal year that began Oct. 1, did include language requiring the Pentagon to study the transition to a new salary-based pay structure that would do away with BAH and Basic Allowance for Subsistence.

The new compensation would focus on salary "compatibility" with the civilian sector, but must cost the Pentagon no more than the current system, the law states.

Two reports, one on transitioning to the new system and the other on how the system would work, were due to Congress by March 1 and by January. But it's common for such documents to be delayed, and the initial report hasn't been submitted yet, Pentagon officials confirmed.The language has caught some troops off guard and spurred them to take action.

Air Force Capt. Chris James said he was alerted to the issue by his chain of command and that he has since contacted his congressional representatives to express his concern over what they suggest.

"This will cause enormous inequities amongst active-duty members who are subject to the state tax withholdings that reflect their home of record," he said in an email to Military.com. "In general, this change will cost all active-duty members tens of thousands of dollars in take-home pay over the course of a career, making it that much harder to provide for their families."

The Heritage document also calls for combining military commissary and exchange stores, and reducing by 20 percent the annual $1.4 billion commissary subsidy -- efforts estimated to save $286 million in fiscal 2018. This proposal has also previously failed to pass Congress.

It's unclear whether the Trump administration plans to reform such military benefits, though his proposal for a military build-up closely mirrored that of the Heritage Foundation. The president's budget request, statutorily due in February, is expected to be released in May.

-- Amy Bushatz contributed to this report.

-- Brendan McGarry can be reached at brendan.mcgarry@military.com. Follow him on Twitter at @Brendan_McGarry.