<p>I got this info from reading CC last year. It deposits your rewards points, which convert to cash, directly into your 529 account. I’m not sure there is a limit because I have not purchased any big ticket item( like a car) using my credit card.
It pays to read CC. :D</p>
<p>EDIT, here is the link.</p>
<p>[Fidelity</a> Investments](<a href=“http://personal.fidelity.com/products/checking/content/529_card.shtml.cvsr]Fidelity”>http://personal.fidelity.com/products/checking/content/529_card.shtml.cvsr)</p>