WASHINGTON — College students taking out new loans for the fall term will see interest rates twice what they were in the spring — unless Congress fulfills its pledge to restore lower rates when it returns after the July 4 holiday.

Subsidized Stafford loans, which account for roughly a quarter of all direct federal borrowing, went from 3.4 percent interest to 6.8 percent interest on Monday. Congress’ Joint Economic Committee estimated the cost passed to students would be about $2,600.

“It’s outrageous,” said Kathryn Butt, 22, is a College of Charleston junior who lives and works at home on Johns Island while she goes to school. While Butt has scholarships and grants to pay for most of her college, she still had to take out student loans to pay for fees, parking, books and other costs that come with school, the basics of living.

“My generation doesn’t have the luxury of starting a life after college. We cannot look at buying property, investing in the stock market, saving bonds. We can’t do anything because we have to dig ourselves out of a hole first.”

She and the millions of others who use federal student loans to pay for their education have some time before she has to worry about next year’s loans. But not much.

“The only silver lining is that relatively few borrowers take out student loans in July and early August. You really can’t take out student loans more than 10 days before the term starts,” said Terry Hartle, a top official with colleges’ lobbying operation at the American Council on Education.

But that is little consolation for students looking at unexpected costs waiting for them on graduation day if Congress doesn’t take action before it breaks again for the month of August.

“I’m upset by it,” said Kolton Gustafson, a George Washington University political science major whose coming senior year will pack twice the interest as his junior year. “I wish there was a larger reaction to it.”

Both political parties tried to blame the other for the hike and student groups complained the increase in interest rates would add to student loan debt that already surpasses credit card debt in this country.

“The federal loan program is burying them in debt. With the doubling of the interest rate, Congress is pushing student borrowers to their limit,” said Michael Russo, federal program director with consumer advocate U.S. PIRG.

“It’s ridiculous,” said Butt. “How do we know that the rates won’t go up again?”

Lawmakers knew for a full year the July 1 deadline was coming but were unable to strike a deal to dodge that increase. During last year’s presidential race, both parties pledged to extend the 3.4 percent interest rates for another year to avoid angering young voters.

But the looming hike lacked sufficient urgency this year and Congress last week left town for the holiday without an agreement. Instead, the Democratic-led Senate pledged to revisit the issue as soon as July 10 and retroactively restore the rates for another year — into 2014, when a third of Senate seats and all House seats are up for election.

Even when lawmakers return, there’s no guarantee there will be the votes to restore the lower rates.

For months, the student loan issue was the subject of partisan sniping — sometimes within the same party.

Obama’s budget proposal included a measure that would have linked student loan interest rates with the financial markets. Fellow Democrats called that unacceptable because there were no guarantees interest rates would not skyrocket if the economy improves.

The Republican-led House, meanwhile, co-opted the president’s proposal and passed a bill in May that linked interest rates to the financial markets but with a cap on how high rates could climb.

The Democratic-led Senate, meanwhile, tried for a two-year extension that failed to overcome a procedural hurdle. A Republican measure, similarly, came up short.

Top White House officials told allies to find any deal that could win enough votes and avert the politically and fiscally costly doubling.

Sandra Bussey Turner, Butt’s mother blasted both parties for the political fingerpointing. “We’re out here working for a living and don’t know the specifics of all of these deals. We need someone who is working for the American people so we can make a living.

“Nobody seems to be on fire to get things done.”