Texas-New Mexico Power (TNMP): TDU Guide

Texas-New Mexico Power (TNMP) is a transmission and distribution utility (TDU) that delivers electricity to approximately 270,000 customers across Texas.^[1] TNMP is a subsidiary of PNM Resources, which was acquired by Avangrid in 2023.

TNMP does not sell you electricity. In Texas's deregulated market, TDUs own and maintain the power lines, transformers, and meters. You choose a retail electric provider (REP) who buys electricity on the wholesale market and sells it to you. TNMP delivers it.

Your electric bill includes both TNMP delivery charges and your REP's energy charges. TNMP's delivery rates are regulated by the Public Utility Commission of Texas (PUCT). Your REP's rates are set by market competition.

TNMP serves a patchwork of communities across Texas, not one contiguous region. Major areas include parts of the Texas Gulf Coast, Central Texas, and North Texas.

Key cities in TNMP territory include Galveston, Texas City, League City, Angleton, Gatesville, Lampasas, and parts of the Bryan-College Station area. TNMP also serves smaller communities in Cooke, Grayson, and Montague counties near the Oklahoma border.

To check if TNMP serves your address, enter your ZIP code when shopping for electricity plans. Your TDU is determined by your physical address, not your choice of REP. If TNMP is your TDU, you will see "TNMP" or "Texas-New Mexico Power" on your bill alongside your chosen provider's charges.

TNMP delivery charges appear on your bill as a separate line item from your REP's energy charges. These are regulated by the PUCT and apply equally to all customers in TNMP territory, regardless of which REP you choose.

TNMP delivery charges include a fixed monthly fee (around $4-5/month) plus a per-kWh delivery rate (roughly 3.5-4.5 cents per kWh). The exact amount depends on your rate class and current PUCT-approved tariff.

When comparing REP plans, look at the Electricity Facts Label (EFL). It shows the all-in price including TNMP delivery charges at 500, 1,000, and 2,000 kWh usage levels. This is the real cost comparison number. Some REPs advertise low energy rates but the EFL reveals higher total costs after delivery.

Shopping for electricity in TNMP territory works the same as anywhere in deregulated Texas. You pick a REP, they handle the rest.

Step 1: Find your TNMP ESID (Electric Service Identifier) on your current bill.
Step 2: Compare plans at ElectricRates.org or the PUCT's Power to Choose website.
Step 3: Review the Electricity Facts Label for each plan. Focus on the price at your typical usage level.
Step 4: Enroll online. Your new REP contacts TNMP to switch service.

The switch takes 1-3 business days for existing service. TNMP continues delivering your electricity without interruption. There is no physical change. Your meter reads the same. Only your energy supplier changes.

Texas has five major TDUs. TNMP is the smallest, but delivery charges vary across all of them.

Oncor is the largest, serving Dallas-Fort Worth and much of North and Central Texas. CenterPoint covers Houston metro. AEP Texas serves Corpus Christi, the Rio Grande Valley, and West Texas. TNMP covers scattered regions including Galveston and parts of Central Texas.

TNMP delivery rates are generally competitive with other TDUs. The differences are modest—usually less than 1 cent per kWh between TDUs. What matters more is which REP you choose, since energy charges vary by 2-4 cents per kWh across providers.

You cannot choose your TDU. It is determined by your address. But you have full choice over your REP within any TDU territory.

Since TNMP owns the power lines, they handle all outage restoration—regardless of your REP.

Report outages to TNMP at 888-866-7456 or through the TNMP outage center online. The outage map shows affected areas and estimated restoration times. Do not call your REP for outages; they cannot fix power lines.

Emergency (downed power line): Call 888-866-7456 immediately and stay at least 35 feet away from any downed wire.

For billing questions, contact your REP, not TNMP. Your REP handles your account, payment, and rate. TNMP only handles delivery infrastructure. If you have a meter issue or need a new connection, your REP coordinates with TNMP on your behalf.^[2]