If it is a federal student loan and you are in default, then they have the ability to garnish your income tax refund. There is no legal manner in which you can prevent them from doing so. However, you may wish to speak to your lender in order to work out a payment arrangement. It is possible that they will consider not garnishing your income tax refund if you can come to an agreement. Nonetheless, you can't prevent them from taking the refund if they refuse to work out an agreement with you.
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