On Tuesday, the Congressional Budget Office will release its assessment of the Senate immigration bill’s effect on the federal budget, a Senate Budget Committee spokesman told the Washington Examiner.

“It will come out tomorrow,” Stephen Miller, a spokesman for Sen. Jeff Sessions, R-Ala., said of the score. Don’t expect the CBO’s report to end the debate about the cost of the Gang of Eight’s proposal, though. Cost estimates by outside groups have proven contentious throughout the debate about the bill, as have the criteria that the CBO should use when developing its score.

“The legislation would enable millions of illegal immigrants to access federal and state welfare and entitlement programs, with the most significant costs occurring outside the 10-year budget window when they would be eligible for green cards and ultimately citizenship,” Sessions wrote to CBO director Douglas Elmendorf after the Gang of Eight introduced their bill in April. “No lawmaker should vote on this legislation until we have a complete and thorough estimation of the long-term cost.”

When the Heritage Foundation predicted that “The Fiscal Cost of Amnesty to U.S. Taxpayers” would be as high as $6.3 trillion over the next 50 years, the long-term cost estimate met with some criticism.

“We have no idea what things will look like in 50 years,” the Tax Policy Center’s Bob Williams said to Factcheck.org. “In the long run, I don’t think we know what the situation will be. It [the $6.3 trillion figure in the Heritage report] is not a number that anyone should put a lot of faith in.”

The Heritage Foundation, as Factcheck.org noted, argues in its report that the CBO’s ten-year cost estimate is misleading because illegal immigrants won’t yet have qualified for government programs; when they do, “former unlawful immigrant households would likely begin to receive government benefits at the same rate as lawful immigrant households of the same education level,” the report states.

When Congress debated an immigration bill in 2007, the CBO “estimated that the legislation would exert a relatively small net effect on the federal budget balance over the next two decades, since additional expenditures would be mostly offset by additional revenue.”