Assuming you and the trust are in Virginia and using a Virginia 529 plan, contributions from a non-owner are deductible by the account owner and not by the non-owner/contributor by state law. I went back in and did a little digging to find Virginia Code § 58.1-322 D 7 states that, "the term "purchaser" or "contributor" means the person shown as such on the records of the Virginia College Savings Plan as of December 31 of the taxable year." To me, this would mean that you would not be eligible to take a deduction for contributions to the account of the trust, because the trust is the owner listed on the account, not you.
However, this is getting into nuanced trust law, so it's really something to discuss with an expert in trust law in Virginia. I know it's a bit of a cop-out on the answer, but trust law can be tricky, and nobody wants a tax "surprise."
Good luck,
Brian Boswell VP, Research & Development
This information does not constitute tax advice and is provided for informational purposes only. Please consult your tax advisor, financial advisor, local taxing authority, and/or plan provider or sponsor for more information.