<p>I can only share my experiences, but when I was a full-time undergraduate from 2004-2008 (ages 18 through 22) my father was providing exactly 0% of my support (everything was covered through scholarships, loans, and work) and I was still covered under his health insurance. Currently I’m 23 years old and my father again is providing exactly 0% of my support and I’m still covered - I provide 100% of my own support through my salary (yes salary, not stipend - it’s a training grant through which I am employed at the school) as a GRA. My dad has also not claimed me on his taxes since I turned 18. And I moved to a different state in mid-2008 - I live in New York, he lives in Georgia. Still been covered for the last 2 years.</p>
<p>Every insurer works differently, but my dad’s insurance company considers me a dependent until I’m 26 years old as long as I can provide evidence that I’m a full-time student. It doesn’t matter how much of my own support is provided by me or my dad. (My dad’s insurance company had this rule even before the healthcare reform, which was awesome of them :D)</p>
<p>You need to talk to your father more about the provisions of his specific insurance plan. I know in my case my dad didn’t know, so I ended up calling the insurance company at the number on the back of my card. Do that, and find out. Then call the school and find out if your 1/2 tuition scholarship/grant/whatever is contingent upon being a tax dependent (which you wouldn’t be) or a dependent student (which you would be until you turn 24 regardless of how much of your own support you provide).</p>