The end of the year brings the holiday season, but for many recent college graduates, it is also the start of payback time.

Students who graduated from college in the spring — and who took out federal student loans to pay for their education — typically face the end of a "no payment" grace period six months later, though some types of loans allow nine months.

This means that for students who graduated in May, loan statements have begun arriving in the mailbox, or will soon.

"It can catch you by surprise if you're not keeping track," said Lauren Asher, president of the Institute for College Access & Success. The institute's latest report on student loan debt found that nearly 70 percent of college graduates in 2015 had education debt, averaging about $30,000 a borrower.

If you think you should be getting loan statements but have not received one yet, this is a good time to check with your lender or "servicer," the company managing the loan. In some cases, the lender and servicer are the same, but often they are not.

Perhaps you have moved and forgot to update your address with the lender — that does not get you off the hook. As Asher noted, the borrower is responsible for keeping the lender informed of where to send statements and other correspondence.

You can check your loan documents and contact the lender listed. Or, if you have misplaced the documents, you can log on to the Education Department's National Student Loan Data System and see a list of your federal loans, with contact information for the servicer.

(To log on, you will need a Federal Student Aid ID — a user name and password combination. If you do not already have one, the website will direct you to create it.)

Keep in mind that the site shows only federal loans, not loans from banks or other private lenders.

Unless they choose an alternative, federal loan borrowers are automatically enrolled in a standard, 10-year repayment plan — usually the fastest, least-expensive way to pay down the loan. Some borrowers may find that when repayment begins, the monthly bill is a stretch — maybe a job pays too little, or living expenses are higher than anticipated.

In that case, the federal government has several flexible repayment plans that offer to lower the monthly payment — in some cases, to zero — by extending the length of the loan or by setting payments based on income.

In some cases, you might even be eligible to have the debt forgiven after 20 to 25 years, or after 10 years if you are in certain public-service jobs.

The plans' rules and criteria vary, so Asher advises using the federal Repayment Estimator to see which plans you qualify for and what the monthly payment would be.

Matthew Ribe, director of legislative affairs with the National Foundation for Credit Counseling, recommends that borrowers always confirm with their loan servicers that they are enrolled in the payment plan they want. And bear in mind, he said, that lowering monthly payments may mean it will take longer to pay off the debt, costing more in the long run.

"You may find that making a low payment means you're not making a lot of progress," Ribe said.

Ann Carrns writes for the New York Times.