It depends, but in most cases, yes. You don’t have to add a cosigner unless you’re under the age of majority in your state (usually between 18 and 21). But if you have a limited or poor credit history, a lender may require you to add a creditworthy cosigner to balance out their risk on the loan.
Plus, more than 90% of private student loans taken out by undergraduate students are cosigned. Even if you’re a graduate student and don’t need one, adding a cosigner with good credit can improve your chances of qualifying for a private student loan at a lower rate.
Credible even makes it easy to compare cosigners to see which cosigner can help get you the best rate.