All New Mexico and foreign LLCs authorized to do business in New Mexico must register with the New Mexico Taxation and Revenue Department and obtain a Combined Reporting System (CRS) identification number. You may register and obtain your CRS identification number online or you may file a paper ACD-31015, Application for Business Tax Identification Number, with any local tax office. See the Taxation & Revenue website for more information. There is no fee to register or obtain a CRS identification number. For more information, see Nolo's Article New Mexico LLC Annual Filing Requirements.
New Mexico also requires pass-through entities, including multi-member LLCs, to file a New Mexico Income and Information Return for Pass-Through Entities (PTE). You must file this form with the state before the due date of your federal tax return and deduct and withhold tax from each non-resident owner's share of net income. For more information, see the New Mexico Taxation & Revenue website. This requirement does not apply to single member LLCs, which are treated as sole proprietorships for tax purposes unless they elect different tax treatment.