New Mexico brokerage account growth calculator

What a taxable index-fund account is actually worth after expense-ratio drag and after New Mexico takes its share of the gain — which, in most states, is not at the federal preferential rate.

New Mexico taxes your gains as ordinary income

There is no state equivalent of the federal preferential rate here — a long-term gain is charged at New Mexico's normal income brackets, exactly like wages. This is the common case, and it surprises people who assume the federal 15% carries over. Long-term capital gains enter New Mexico net income through federal AGI and are taxed at the graduated rates above; the federal preferential long-term rate does NOT carry over. IMPORTANT CAVEAT, flagged rather than smoothed over: New Mexico's Income Tax Act does contain a net capital gain deduction at Section 7-2-34 NMSA 1978, historically the greater of a fixed dollar floor or a percentage of net capital gain, and that provision was narrowed by recent legislation. The current amount could not be confirmed from a primary source within this pass, so no exclusionPct is recorded — see NEEDS_VERIFICATION. Treat 'ordinary' as the conservative floor: a New Mexico taxpayer with a large long-term gain may owe less than the ordinary-rate calculation implies, never more.