Yes, federal student loans can be deferred during grad school (it's NOT automatic of course, you have to do a little bit of paperwork). If they're subsidized they will not generate interest while they're in deferment. Private loans I'm guessing will depend on the lender. I didn't consolidate mine. I have ~$20k in undergraduate loans, mostly subsidized Stafford loans handled by Sallie Mae. They're at a 3.61% interest rate, but again most are not generating interest right now. My strategy has been just to pay $50 a month into my loans, which eats up the interest and a little bit into the principal. Definitely pay enough to cover the interest if you can, any money spent on student loan interest payments is tax deductable.