To accurately determine the correct amount of Massachusetts withholding, employers will rely on Massachusetts Form M-4. The proposed Massachusetts withholding tax regime requires the collection of tax on the net gain arising from the sale or transfer of Massachusetts real estate.Massachusetts source income is generally taxable to non-residents. The Massachusetts source income derived from New York LLC, determined pursuant to the allocation and apportionment rules of 830 CMR 62.5A. Upload your W-2 file in your Withholding account in Taxation's portal, or; Send your W-2 file on a CD or DVD to the R.I. Division of Taxation.