Saving for college in a 529 plan offers state tax benefits and other perks—but they vary widely by state. When deciding on a 529 plan, you should consider the potential tax benefits as well as the investment options and fees for any given plan.
The map above from the Wall Street Journal is an old one (2011) showing the state tax savings using a hypothetical example of a couple making contributions of $2,500 a year for each of two children. It shows how some states offer incredible tax savings, compared to others—so if you live in Indiana, Vermont, or Iowa, you'll most likely benefit more from using an in-state 529 plan rather than choosing an out-of-state one.
Morningstar has updated (October 2014) 529 plan details per state, noting the deduction credit limit. In their scenario, they're calculating the dollar tax benefit for a couple filing jointly with a $50,000 income and two children for whom they contribute $1,200 a year ($2,400 total):
The lower the value of the tax benefit, the more you might want to shop around to find the best 529 plan for you.
Staying Local Benefits College Savers in These States | Morningstar via My Money Blog