Like consumers and homeowners, America’s corporations binged on easy credit when times were flush, racking up huge debts. Now the bills are due, and paying them back will not be easy, or cheap.

This year alone, more than $700 billion in corporate loans will come due, according to Standard & Poor’s. That is the size of the federal bailout of the financial sector. Many companies were counting on being able to borrow more money to meet those obligations and kick their debt farther down the road.

But with the credit markets still tight, corporations are being forced to pay much higher interest rates than they did a few years ago, putting more strain on balance sheets already hammered by falling profits and a grinding recession.

It is a lesson the discount carrier Southwest Airlines learned firsthand in December, when it went to the bond markets to raise $400 million, in part to cover its losses from betting that fuel costs would stay high.