I am unable to find any guidance from New York regarding the use of a 10-digit code instead of a 15-digit code.
On the SUNY Plattsburgh website FAQ section, a 15 digit number is still referenced. Please see: SUNY Charitable Tax Credit Program.
I recommend contacting the SUNY Impact Foundation directly to see if they are able to provide you with a 15-digit code. Contact info: 212-364-5788 or impactfoundation@suny.edu.
As a workaround, you can try using five zeroes before your 10 digit tax receipt number.
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