Skip to main content

Understanding Loans: Supplemental Private Student Loans

Supplemental private student loans are one way students and families can fill the gap between available student financial aid — including federal student loans — and the total cost of college.

Private student loans must be repaid with interest. They are a serious financial obligation and typically cannot be discharged in bankruptcy.

Interest Rates, Fees and Benefits

Like other loans, private student loans have either a fixed or variable interest rate that is set by the lender. If you take out a Partnership Advance Education Loan from ISL Education Lending, you choose either a fixed or a variable interest rate and select your preferred repayment option when you apply. Interest accrues daily on student loans.

Private student loan borrowers may be charged fees, such as an origination or late fee, but may also qualify for benefits, such as interest rate or principal balance reductions and cosigner releases.

Interest Charges

Interest accrues daily based on the principal balance of student loans as of that day and the interest rate.

Interest is calculated on student loans through a simple interest method using the following formula:

Principal balance x (interest rate / number of days in this year) x days since last payment = interest that has accrued since the last payment

For example, if you have a loan with a principal balance of $10,000 with a 6.40% interest rate and it has been 30 days since your last payment, your new outstanding accrued interest would be calculated as:

$10,000 x (0.064 / 365) x 30 = $52.60


Depending on the terms of the private student loan you choose, you may need to make some sort of monthly payment while in school — such as interest-only payments — or you may defer any repayment until after you graduate. Deferring payments for an extended period of time, such as postponing payments while you're in school, may substantially increase your loan balance before any payments are due because of interest that accrues during deferment. We strongly encourage you to make payments that at least cover your accrued interest to avoid increases in your loan balance.


Traditional-age college students may need cosigners to qualify for a private student loan if they don't have the credit history to qualify for the loan on their own. Even if a borrower can qualify for a private student loan on his or her own merit, a cosigner may help the borrower qualify for a loan with a lower interest rate.

Fixed and Variable Interest Rates

Private student loans have either a fixed or a variable interest rate, which is published with the other loan terms when you take out the loan.

Fixed interest rates are set for the life of the loan and cannot change. Under standard or regular repayment plans, if you pay your minimum payment on time each month, every monthly payment amount will remain the same.

Variable interest rates are determined using a formula, usually a set interest rate plus a market rate index such as Prime or Libor (London Interbank Offered Rate). Variable rates may change daily, monthly, quarterly or annually depending on the formula used. Because these rates may fluctuate over time based on financial markets, your minimum monthly payment amount may change based on the rate being charged for that time period.

If you take out a Partnership Advance Education Loan from ISL Education Lending, you choose either a fixed or a variable interest rate and select your preferred repayment option when you apply.

Share this article

Sign up for college planning information

Subscribe now

Related Articles

Find this article interesting? Check out the articles below on similar topics.

Understanding Loans: Reduce Loan Costs

The easiest way to reduce any student loan costs is by eliminating loans completely or by borrowing a minimal amount. Here's how you can reduce your need for student loans.

Understanding Loans: Credit Scores and Loans

The process of transferring from one college to another can be painstaking and time-consuming. These tips can help you transition more easily.

Understanding Loans: Student Loans and Interest

If you plan to earn money by working in college, you'll need to understand the first steps to finding a job. Here are the basics.