An ESI ID, short for Electric Service Identifier, is the number that identifies your meter’s location in the Texas electricity market. Every address in the part of Texas that chooses its provider has one, and it is printed on every electricity bill. It belongs to the premise, not to you and not to your provider, so it stays the same when you switch plans or when the home changes hands. When a provider, the delivery utility or ERCOT needs to say “this meter, at this address,” the ESI ID is how they say it.
What it is, and what it isn’t
Three parties handle your electricity: the retail provider that bills you, the delivery utility that owns the wires and the meter (Oncor, CenterPoint, AEP Texas, TNMP or Lubbock Power & Light), and ERCOT, the grid operator that passes orders between them. All three use the same ESI ID for your address. Your account number, by contrast, is issued by the provider and changes every time you switch. The meter number, printed near the ESI ID on most bills, identifies the physical device on the wall; the ESI ID identifies the place.
What it looks like
A long string of digits, with no letters. The length depends on the utility: 17 digits in Oncor, AEP Texas and TNMP territory and 22 digits in CenterPoint’s, as the utilities and comparison sites describe it. Bills label it “ESI ID,” “ESIID” or “ESI-ID.”
Where to find yours
| Source | Where to look |
|---|---|
| Your bill | Near the service address, or in the delivery or account details; on paper and PDF alike |
| A previous occupant’s bill | Same number; it belongs to the address, so an old bill left in the mailbox has it |
| The leasing office or seller | Often kept on file for the unit, especially in large complexes |
| Any retail provider | Can look it up from the address while you enroll, without a bill |
| The delivery utility | Can look it up from the address; the meter is theirs |
If you have never had service at the address and have no bill, the provider’s address lookup is the normal route. Have the unit number exact; a lookup that returns the wrong unit is how a neighbour’s meter ends up on your order.
What it’s used for
- Switching. The new provider submits a switch to ERCOT against the ESI ID, and ERCOT tells the delivery utility and the old provider which meter changes hands and when. See how to switch.
- Moving in. Same mechanism: the provider submits the move-in to ERCOT, which notifies the utility, and the meter is connected remotely. See setting up electricity when you move.
- The switch-hold check. A switch-hold sits on the premise, not the person: the utility places one after meter tampering, a provider may place one when a customer behind on payments enters a deferred payment plan. Orders against that ESI ID are rejected until it is lifted; for a new occupant, the new provider asks the utility to lift it after confirming you are unrelated to the last one.
- Outage reports. The utility, not the provider, restores power, and the ESI ID tells it exactly which meter is dark.
- Smart Meter Texas. The free usage-data site run by the utilities asks for the ESI ID and the meter number to open an account, and then gives you monthly, daily and 15-minute readings for the address. See how to find your kWh usage.
Is it sensitive?
Not a secret, but not nothing. Any provider can look it up from the address, and giving it to a provider or a comparison site for a quote is normal. What it enables is the problem: an ESI ID, a name and a start date are most of what a switch order needs. Treat an unsolicited caller or door-knocker who asks for it the way you would treat one asking for your account number. If a switch you didn’t order does show up, Texas rules give you three federal business days after you receive the terms to rescind it without penalty.
Why WattaWatt doesn’t ask for it
WattaWatt never submits an order to a provider, so it has no use for the number. It reads the usage history on your bill, prices every plan sold at your ZIP code on those months and shows the math; the file is read and discarded. When you pick a plan, you enroll on the provider’s own site, and that is where the ESI ID is needed, by you or by the provider’s address lookup.
To compare plans, upload a bill or type your last 12 months of kWh; new to the address with neither, start from the rates pages’ small, typical or large home and refine the numbers after your first summer.