2023 Publication 17, page 23 https://www.irs.gov/pub/irs-pdf/p17.pdf , in the case of married filing separately, 'NRA' can be used in the space of the non resident foreign spouse's SSN for a foreign spouse who does not have and is not required to have a SSN or ITIN. Why can Turbotax modify the form online to accommodate a value 'NRA' in the SSN filed for such scenario?
