Paycheck parking means your pay lands on a balance that charges you interest, so the balance is lower every day until you pull the money out for bills. A viewer asked me whether the same thing works on a student loan. It doesn't, and the reason is in the second half of that sentence.
A student loan is an installment loan. That means you borrowed a fixed amount and you repay it on a schedule. Once you send extra money to it, the lender keeps it. There's no button that sends the money back out to your checking account.
Try it on paper. You owe $30,000 at 7% and your $4,000 paycheck goes straight onto the loan. The balance drops to $26,000, and those two weeks cost about $11.50 less in interest. Then rent is due. The $4,000 is gone, so you cover rent with a credit card or an overdraft, and both usually cost far more than 7%.
A line of credit is different because it's revolving. That means you can pay it down and borrow from it again as often as you want. Your pay can land on it, lower the balance for the days it waits, and leave again when a bill arrives. I answered this question in a short video about using Dynamic Banking on student loan interest.
Some people ask about sending a lump sum to the student loan every payday instead. That does work as a one-way payment, and it's fine if you keep a separate cushion for bills. It just doesn't offset interest on your spending, since the money can't come back out.
So the line of credit is the hub and the student loan is the target. Your pay goes onto the line of credit and your bills come off it. Every so often you draw a lump sum from the line of credit and send it to the student loan. That lump sum is called a chunk. The line of credit stays open for your bills, and the student loan balance steps down.
Before you chunk, check two things. First, compare rates. If your line of credit costs more than the student loan, the chunk moves debt onto a more expensive home, and chunking when the line of credit costs more than the loan shows how to test that. Second, ask your loan servicer what you give up. Federal student loans can carry income-based payment plans and other protections, and paying one off early ends them. I'm not an attorney or a tax professional, so confirm the details with your servicer.
Chunking car loans and student debt uses the same moves as a mortgage, and that post compares the targets side by side.
Log in to your servicer this week and write down the interest rate on each student loan, because the highest rate is where your first chunk should point.