The House adopted its fiscal 2018 budget resolution Thursday, five days after the fiscal year began Oct. 1.

The 219-206 vote, which moves Republicans one step closer to the reconciliation instructions they need to advance a tax bill through the Senate without Democratic support, was largely along party lines, although 18 Republicans defected and voted against the resolution. No Democrats voted for the GOP-drafted budget plan.

The House now must wait for the Senate Budget Committee to finish marking up its budget resolution later Thursday, and for the Senate to hold a floor vote later this month, before the two chambers can conference their significantly different budgets.

While the topline spending levels in this year’s budget resolution don’t matter — a bipartisan budget agreement must be signed into law to raise statutory spending levels — agreement on the reconciliation instructions will have a substantial impact on the tax-writing committees.

The House budget calls for a deficit-neutral tax bill and at least $203 billion in mandatory spending reductions during the next decade. The as-yet-unnumbered Senate budget resolution would allow the GOP tax bill to increase deficits by $1.5 trillion during the next decade, and sends instructions to the Senate Energy and Natural Resources and House Natural Resources committees to reduce spending by $1 billion during the same time frame.

The Energy panel instructions are widely expected to yield legislation that would open a portion of Alaska’s Arctic National Wildlife Refuge to oil and gas exploration, bringing in federal lease revenue.

What the reconciliation instructions say will affect the final budget votes in each chamber.

The Senate GOP already has a thin margin through which to thread the needle. Majority Leader Mitch McConnell of Kentucky can lose no more than two Republicans before the budget — and the tax bill — would stall.

The House GOP Conference would need the votes of the Freedom Caucus to pass a final budget. The conservative group had called for as much as $400 billion in mandatory spending cuts earlier this year, when the House budget was still being drafted.

Freedom Caucus Chairman Mark Meadows has indicated his members recognize the need to adopt a budget resolution so a Republican tax bill can avoid a filibuster.

“The real trade-off is how aggressive you get with tax reform, which I think we are going to be aggressive with tax reform — perhaps at the expense of mandatory spending cuts,” the North Carolina Republican said last week. “And I think generally we see an aggressive tax reform policy placed into law as certainly our top priority, with maybe a secondary priority being the mandatory spending cuts.” 

Until a final budget resolution is adopted, congressional Republicans cannot officially begin to advance their tax bill.

House debate on the budget, which lasted about two days, largely centered around the potential impact of the GOP tax outline and proposed changes to mandatory spending programs.

House Budget Chairwoman Diane Black touted the resolution as a conservative tax and spending document that would allow a unified Republican government to work toward its campaign promises.

“Are we proud of a country where we are leaving our children and grandchildren in further and further debt?” Black asked, later adding that “without question,” the Republican plan reflects American priorities and shared values.

Democrats, on the other hand, criticized the budget blueprint and the unreleased tax bill as proposals that would help the wealthy at the expense of safety net programs while adding to the debt.

“This plan is a hoax on the American people and it will make most people’s lives more difficult, so forgive me if I am in no mood to say thank you for the extra money in my pocket,” said top Budget panel Democrat John Yarmuth, referring to the extra income he may be able to keep under a GOP tax overhaul. “With this budget, Republicans are not just passing the buck, they are pocketing it.”

Before its final vote, the House considered and voted down several alternative budget plans. On Wednesday night, the House rejected a proposed alternative from the Congressional Progressive Caucus, 108-314, and another from the Congressional Black Caucus on a 130-292 vote. Prior to final adoption Thursday, the House rejected the Republican Study Committee alternative budget on a 139-281 vote, while the Budget Committee Democrats’ version went down to defeat on a 156-268 vote.