Greenlight · Level 2 auditing

Lesson 5 of 9

Anatomy of a tariff

Rate schedules, availability, riders, and why several versions are live at once.

The short version

A tariff is the utility’s public price book, approved by the state. If a charge is not in it, the utility cannot make it.

Everything a regulated utility charges has to be written down, filed, and approved before anyone is billed for it. The result is the tariff: a long, dull, completely public document that contains the answer to almost every question you will have. You can download it from the utility’s website, usually under “Rates and Tariffs”, or from the state commission. You do not need the customer’s permission to read it.

Step 1

The utility publishes its prices and the state approves them.

The tariff is approved by the state commission The tariff State commission approves every price
That approval is why the document is public, and why you can trust it over anything a rep tells you on the phone.

Step 2

Inside are rate schedules — the price plans.

One tariff contains several rate schedules One tariff Residential Small general Large general each one has availability prices a minimum bill terms of service
Read those four sections in that order, every time. The prices are the third thing you look at, not the first.

Step 3

Availability decides who may take a rate.

Two rates unavailable, one available Rate A needs 500 kW too small Rate B 50 to 400 kW ELIGIBLE Rate C residential only wrong class
A cheaper rate the customer is not allowed to take is not a finding. It is a waste of everybody’s afternoon.

Step 4

Riders attach extra charges and programs.

Three riders attached to one rate Rate GS-2 Rider A — automatic Rider B — automatic RIDER C — YOU MUST APPLY
Nobody signs up for something they have never read. That is exactly why the optional ones are worth money.

Step 5

Sheets get revised, so several versions are live at once.

Three tariff versions with different effective dates Version 1 to Dec 2023 Version 2 2024 to 2025 Version 3 current THE ONE THAT COVERS YOUR BILL
The newest version is almost never the one you want. You want the one that was in force during the bill’s service period.

How to read a rate schedule

  1. Availability. Who may take this rate. Customer class, size limits, demand floors and ceilings, voltage, sometimes location. This is a gate, and it comes before any pricing question.

  2. Monthly rate. The actual charges — the customer charge, the per-unit rates, the demand rate, any blocks or seasons.

  3. Minimum bill. The floor. Below a certain point the customer pays the floor no matter how little they use.

  4. Terms of service. Contract length, how much notice is needed to switch, and how often the customer is allowed to switch at all. This is the section that decides whether a finding is actionable this year or next.

Rate families

Most tariffs run the same ladder: residential, small general service, large general service, primary or transmission service, industrial, and a lighting schedule for streetlights and signs. Alongside those you will find seasonal rates, where summer and winter prices differ, and time-of-use rates, where the price changes by hour of day.

Riders

A rider is an add-on attached to a rate — an extra charge, a credit, or a whole programme. Some are mandatory and land on every bill automatically. Some are optional and the customer has to apply. Other names for the same thing: adjustment clause, surcharge, tracker, mechanism.

Riders are where a lot of Level 2 money hides, for a boring reason: an optional rider only helps people who know it exists, and the tariff is the only place it is written down.

Dates, and why there is more than one live version

Tariff pages are called sheets, and they get revised one at a time. A sheet carries an effective date (when these prices start applying), often an issued date (when it was filed), and a note saying which sheet it supersedes. So at any moment the utility has a current version and a trail of older ones, and a bill from eighteen months ago belongs to one of the older ones.

Watch the wording

“Effective for bills rendered on or after 1 June” is not the same as “effective for usage on or after 1 June”. The first changes the price of a bill that covers May. The second does not.

Two small things that cost people hours

Aliases. The bill says GS-2. The tariff says Rate Schedule GS-2 — General Service Secondary. The bill says Rider CIP. The tariff calls it the Conservation Improvement Program Rider. Same thing, different length. Expect this and search for the short form.

Supplier prices are not in the tariff. In a deregulated state the tariff covers delivery, and the utility’s default supply price. A third-party supplier’s price lives in a private contract, which you have to ask the customer for.

The one thing to remember

Availability decides what the customer may take. Price decides what they should take. Read availability first.

Check yourself

Where do you find a utility’s tariff, and do you need permission?

On the utility’s website or the state commission’s site, and no. It is a public filing.

What is a rider, and why do the optional ones matter to us?

An add-on charge, credit or programme attached to a rate. The optional ones only apply if the customer asks for them, and almost nobody reads the tariff, so they go unclaimed.

A bill covers March 2024. The tariff on the website was revised in January 2026. Which do you use?

Neither one blindly — you go and find the version that was in force in March 2024.

Which section of a rate schedule tells you whether the customer can act on your finding this year?

Terms of service — contract length, notice period, and how often switching is allowed.

← Lesson 4 Lesson 6 → Matching the bill to the tariff