I am a non-resident (NJ) filer with income from NY and am funding our kids' 529 plans under the NY 529 plan (deduction code S-103 on the IT-225). In years past (when not efiling), I have been able to allocate the 10,000 deduction against NY income, but Turbotax is not allowing this when trying attempting to efile. I believe I should be able to allocate the deduction against NY income, but TT won't allow this or an override to efile. I may just end up mailing in the return if it's not something that can be fixed.
Instructions changed for non-residents, you can no longer allocate any to the NY amount. IT -225 instructions https://www.tax.ny.gov/pdf/current_forms/it/it225i.pdf
Form IT-203 filers: If in 2018 you, as an account owner, made
contributions to one or more tuition savings accounts established
under New York’s 529 college savings program, then enter
that amount, up to $5,000 for an individual, head of household,
qualifying widow(er), or married taxpayers filing separately, or up
to $10,000 for married taxpayers filing a joint return, in the Total
amount column only.
Part-year resident individuals only: Also enter in the New York
State allocated amount column any such contribution(s) made
while a resident of New York State