Several of Chicago’s 130 charter schools fear they won’t be able to afford to reopen their doors in the fall if proposed budget cuts from Chicago Public Schools become a reality.

CPS has said it may have to cut per pupil funding by about 43 percent compared to last year as Illinois’ largest school district lobbies state legislators for financial help. District schools will see a loss of about one in four dollars on average once their federal and state money shakes out.

CPS has warned some principals to expect drastic cuts to the amount of money the district allocates per student. For fourth- to eighth-graders, that sum will fall from more than $4,000 to $2,495 whether the student attends a district-run or charter school.

CPS spokesman Michael Passman said none of the charters have informed the district they cannot open in the fall.

For some charters, that plunge in funding per student will be more than they can handle, said Andrew Broy, of the Illinois Network of Charter Schools. Of Chicago’s 60,000 children in publicly funded but privately managed schools, up to 15,000 students could be affected “if we truly have the doomsday scenario,” he said.

That’s partly because of costs unique to charter budgets that aren’t flexible, such as facilities leases, Broy said.

“Several dozen schools would be pushed over the brink,” he said, declining to name any. But he said that generally “the smaller schools and the single campuses are more precariously situationed” because they often lack reserves and can’t spread their losses among campuses.

The problem with any schools closing abruptly is that their parents would have to scramble to find places to send their children, and other schools would have to suddenly accommodate them.

The funding drop also would affect prospective operators of new charter schools still seeking to open schools in the troubled district next fall, so CPS just extended the deadline for those proposals until July, citing “CPS’ ongoing fiscal challenges, recent budget reduction estimates provided to District-run schools and efforts to secure equal funding from Springfield.”

CEO Forrest Claypool is heading to the state capital on Thursday, and he has encouraged students, teachers and parents to join him in pressing lawmakers to act on school funding legislation before the session ends on May 31.

The Noble Network of Charter Schools, a large local chain of mostly high schools, said it will be able to weather the cuts and open a new high school in September that will end up on the Southwest Side.

“Cuts in any form will be painful but we’re still planning on our schools opening on time, including Mansueto which will open in a temporary site for the first year,” spokesman Cody Rogers said.