College can be expensive, especially if students attend a public university in a state other than which they live. The College Board reports that, for the 2012-13 school year, the annual full-time rate for an in-state student at a four-year public university was about $8,600, while out-of-state students paid around $21,700 per year. With this drastic cost difference, it's no wonder some out-of-state students wonder if there are ways to qualify for cheaper in-state rates.

How Residency is Determined

Many schools have rules in place to prevent students who live in other states from easily qualifying for in-state tuition. Most schools consider students to be "in-state" if they graduated from an in-state high school or if their parents live in the state. Some allow students who have worked and lived in the state for at least a year qualify for the in-state rates, as long as they can prove their residency by voting in local elections, having a state driver's license or paying state taxes.

Look for a School in a Common Market

The Daily Finance and authors Sandy and Matthew Botkin report that in some areas of the country exist "academic common markets." In these areas, states have agreed to offer in-state tuition rates to students within their market. Currently, there are four markets in the United States covering all areas of the country. Beware though -- students can only qualify for in-state tuition in another state if their major not offered by any public school in their home state.

Become Independent

If students can prove they are independent of their parents by showing they have the finances to pay for school, some states may offer instant residency. If students go this route, they need to make sure they register to vote and pay state taxes. Another caution here -- if a student declares himself independent, he can no loner be claimed by his parents on an income tax return.

Join the Military

While it may seem drastic, joining the military may be a viable option for some students. Not only will you be eligible to use funds from the GI Bill for your education, but you can choose to attend college in the state you call your legal permanent residence as well as the state where you are stationed. The National Military Family Association reports that service members on active duty for at least 30 days, or their spouses, can receive in-state tuition as long as they stay enrolled, even if they are transferred to another state.

Narrow Your Search

If you are dead-set on attending an out-of-state college but can't afford the higher rates, consider colleges that do not charge different rates based on residency. Eastern Oregon University costs the same for both in-state and out-of-state students and Minot State University in North Dakota charged all students $6,000 in 2012. According to U.S. News and World Report, West Texas A&M University, Northern State University, Midwestern State University and the University of South Dakota are some of the cheapest colleges for out-of-state students.