I am currently on the Income Based Repayment Plan with Sallie Mae. I am unemployed right now and want to file a joint return with my husband. Our income together would raise my payment to over $400 per month. Can I claim a unemployment deferment so we can file taxes together?

You can if you want…an IBR is a payment plan and like any other payment plan can be placed by deferment.  Two things to consider.  First off the government pays your subsidized interest for the first 3 years on an IBR and that clock runs whether you are in Deferment or not (with one exception) and you only get 3 years total of Unemployment Deferment so be judicious