Where Green Button Works: Utility Coverage and Certification Across North America

One of the first questions teams ask when they plan an energy data project is simple: does my utility support Green Button? The honest answer is that there is no single answer. Green Button is a standard, not a national service, and each utility decides whether and how to implement it. Two customers in different provinces or states can both say their utility offers Green Button and mean quite different things. This guide explains how coverage actually works across North America, what the two access modes require, and how to read Green Button Alliance certification so you know what a utility has really committed to.

What it means for a utility to support Green Button

Green Button is built on the North American Energy Standards Board (NAESB) Energy Services Provider Interface, known as REQ.21 or ESPI. The Green Button standard defines a consistent XML format for energy usage data so that a file from one utility is structured like a file from another. That uniformity is the value: you write your ingestion logic once. What is not uniform is whether a given utility has implemented it, and in which mode.

There are two modes, and a utility can support one, both, or neither. Download My Data is the manual export a customer pulls from the utility portal as a file. Connect My Data is the authorized, ongoing feed that a customer permits a third party to receive directly from the utility through an API. A utility that offers a download button does not automatically offer the automated feed, so it pays to confirm which mode you are actually getting before you design around it.

What Green Button Alliance certification verifies

The Green Button Alliance (GBA) runs a testing and certification program for utilities. When a utility passes, its implementation earns a Green Button Certified mark for Download My Data, Connect My Data, or both. The GBA testing program checks that an implementation actually conforms to the ESPI standard, so that data from a certified utility will work with standard compliant applications and that the authorization and privacy mechanics behave as specified. Testing is done remotely and takes a few hours.

The program has real reach. As of a July 2023 milestone, the GBA reported that more than 75 Green Button implementations had been certified as compliant, spanning investor owned utilities, community choice aggregators, municipalities, and other providers across the United States and Canada. Certification matters because it turns a marketing claim into a tested fact: a certified implementation has been checked against the standard rather than merely described as supporting it.

One clarification worth stating plainly, because it is often muddled: certification applies to a utility's or a platform's implementation of the standard. It is a fact about that organization. EZGB (Easy Green Button Connector) works with Green Button data from the utilities that provide it, and it does not itself hold or claim any Green Button certification. When you read that a utility is certified, that is the utility's status, not a claim about the connector you use to reach it.

Where coverage is strong

California

California was an early mover. Privacy and data access rules the California Public Utilities Commission adopted in Decision 11-07-056, implementing state law, required Pacific Gas and Electric, Southern California Edison, and San Diego Gas and Electric to give authorized third parties access to a customer's usage data once the customer consents, using a common data format aligned with national standards work. That is the regulatory foundation that made the automated feed possible for the state's large investor owned utilities. San Diego Gas and Electric, for example, offers both Green Button and Green Button Connect My Data to registered customers today.

Ontario

Ontario went further and made it a provincewide requirement. Under Ontario Regulation 633/21, the province's larger electricity and natural gas utilities must implement Green Button. The GBA has since announced that 55 Ontario based utility platforms are Green Button Certified, which is why Ontario is one of the most consistently covered regions in North America for both access modes. The GBA has also documented that Ontario's energy data regulation requires utilities to implement Green Button.

If you are mapping out which of your accounts can be connected and which will need manual exports or bill digitization, tell us the utilities and regions in scope at ezgb.ca and we will help you sort them into the right access path before you build.

How to check a specific utility

For any given utility, a short checklist tells you what you are working with:

Look for Green Button on the utility's customer portal. A download option means Download My Data is available.
Check whether the utility appears among GBA certified implementations, and note whether the certification is for Download My Data, Connect My Data, or both.
Confirm the mode you need. An export button does not guarantee an authorized API feed, and the feed is what recurring products depend on.
Ask about scope: which commodities (electricity, gas, water), how much history is available, and how often new reads and bills post.

Even where a utility is certified, details vary between implementations. History depth differs, some utilities expose interval data while others provide monthly billing detail, and refresh cadence follows each utility's own posting schedule. None of that is a defect; it is the reality of a standard implemented independently by hundreds of organizations.

The role of a connector across many utilities

Certified platforms exist to sit between third parties and utilities. GBA member UtilityAPI, for instance, had its data exchange platform certified as Green Button Connect My Data compliant. The general idea is the same across such tools: rather than register and maintain a token set with every utility yourself, you integrate once and receive a consistent feed. EZGB follows that pattern for the utilities it covers, using both Download My Data and Connect My Data, and for accounts whose history only exists as bill PDFs it turns those bills into structured data in the same shape through BillScan. The result reaches you by REST API, CSV, or SFTP, so your application sees one format regardless of which utility the data came from.

The practical takeaway is to treat Green Button as a coverage map, not a guarantee. Confirm the mode and scope per utility, use certification as evidence rather than a claim, and plan a fallback (manual export or bill digitization) for the accounts a feed cannot reach yet. Do that, and energy data collection becomes a predictable project instead of a series of surprises.

Sources

Source: greenbuttonalliance.org