You might think you don't need disability insurance if you have coverage through work. But in most cases, that only covers around 50-60% of your income—and only for a certain amount of time. Plus, you'll have to pay taxes on any payments you get from that coverage. But when you have your own policy, you can get closer to having 100% of your income covered, the payments you get will not be taxed, and you'll stay covered even if you change jobs. Calculate your coverage amount.