Golden State Water Company is proud to provide reliable, quality water service to communities throughout California. As a regulated utility, we are held to the highest standards of accountability, and we believe it’s important to educate our customers to fully understand their water bills.

We encourage customers to review the information and resources on this page. Customers who have additional questions about their water bills or other regulatory matters are asked to contact our 24-hour Customer Service Center by emailing or calling 800.999.4033 (TTY: 877.933.9533).

Tariff Sheets

A tariff schedule book (tariff) is a pricing schedule or rate plan that regulated utilities like Golden State Water offer to its customers. Along with the pricing plan, there may be certain rules for each tariff a regulated utility offers. Each regulated water utility in California has its own tariffs, which outline approved service areas, rates and conditions of service, and defines the utility’s responsibilities and authorities, among other things. Tariffs, as well as any changes to existing rules, are subject to approval by the California Public Utilities Commission (CPUC).

To learn how to read your tariff sheet, click here.

To view the current tariff sheets for your community, please select your community from the list below and click on the Rates & Accountability menu (far right of page).

Ratemaking Process

As a regulated utility, Golden State Water’s rates are determined by the California Public Utilities Commission (CPUC). The rates reflect the full cost to provide water service, maintain the infrastructure and make needed system improvements.

Golden State Water is subject to state and federal requirements that guarantee the highest levels of accountability and transparency. Additionally, the CPUC provides ongoing oversight and audits of finances, operations and water quality initiatives.


General Rate Case

A General Rate Case (GRC) is a regulatory proceeding conducted by the California Public Utilities Commission (CPUC) to determine rates for regulated utilities. Every three years, the CPUC conducts an open and transparent review of Golden State Water’s rate proposal to ensure customers receive a fair rate for reliable, safe water service.

The GRC process is very thorough and generally lasts 18 months with oversight from the Office of Ratepayer Advocates, a division of the CPUC that scrutinizes the filing on behalf of customers. The utility’s customers have an opportunity to participate in the GRC process by attending Public Participation Hearings and/or testifying in a public proceeding before an Administrative Law Judge.

To learn more, please click here.
For a schedule of Public Participation Hearings, please click here.

WRAM/MCBA Balancing Accounts

During the General Rate Case (GRC) process, the California Public Utilities Commission (CPUC) forecasts water usage in order to calculate rates that ensure revenue recovered from rates balances with expenses to operate, maintain and improve the water system. A large portion of these costs are fixed, meaning that they don’t change as usage changes. Companywide, fixed costs average 76 percent of Golden State Water’s utility expenses.

When water usage does not match the forecasted level and the revenue collected either exceeds or falls short of the CPUC-authorized amount, the Water Revenue Adjustment Mechanism (WRAM) and Modified Cost Balancing Account (MCBA) are used to achieve the financial balance. These tools ensure under-collected revenue is recovered with a temporary surcharge, and revenue that exceeds the authorized amount is returned to customers in the form of a temporary surcredit.

The CPUC model prohibits regulated utilities from keeping reserves or permanently changing rates when revenue fails to cover operating expenses during periods of reduced usage. Rather, the WRAM and MCBA ensure the revenue collected matches the amount authorized by the CPUC to continue providing reliable, quality water service—not a penny more, not a penny less.

The WRAM surcharge is offset by the MCBA, which represents savings in purchased water and energy costs that can result from reduced usage levels.

This process provides transparency and accountability, but can also present challenges during times of drought and reduced water usage.

Given the recent drought and unprecedented statewide conservation requirements, water utilities in every community must make adjustments to account for revenue shortfalls resulting from reduced usage. This is a challenge for all water providers, regulated and municipal.

Please click here to learn more about WRAM/MCBA balancing accounts and the drought’s impact on water bills.

Adjustment For New Federal Corporate Income Tax Requirement

Golden State Water Company (Golden State Water) recently filed to decrease water rates for all service areas to pass cost savings from the new lower federal corporate income tax requirement through to customers. If approved as submitted to the California Public Utilities Commission (CPUC), the new rates will take effect on July 1, 2018.

The Tax Cuts and Jobs Act of 2017 lowered the nation’s federal corporate income tax rate from 35 percent to 21 percent, effective January 1, 2018. As directed by the CPUC, Golden State Water is tracking the impact of the new corporate tax rate and other changes in tax law, and will submit a separate filing to credit customers for any revenue surplus resulting from the reduced tax expense during the period from January 1 – June 30, 2018.

The new federal corporate income tax rate will also lower rates proposed in Golden State Water’s General Rate Case filing for 2019-2021. Golden State Water is working with the CPUC to adjust the rate proposal and revenue requirement to reflect the lower tax requirement, which was signed into law after the rate case was filed in July 2017.

To view the rate decrease for your area, please select your community from the list below:

Surcharges & Surcredits

Golden State Water has developed a resource that provides detailed information on all surcharges and surcredits that are factored into water bills.

Please click here to link to our Surcharges & Surcredit Guide.


Staged Mandatory Water Conservation & Rationing (Schedule 14.1)

In response to local water supply conditions, Staged Mandatory Water Conservation & Rationing (Schedule 14.1) is in place for the Cypress Ridge, Edna Road and Nipomo water systems.

The Staged Mandatory Water Conservation & Rationing (Schedule 14.1) filings outline restrictions, water allocations, enforcement measures and surcharges designed to achieve reductions due to water supply shortages or to achieve identified water usage goals established by an authorized government agency or official.


Assistance For Low-Income Customers

Golden State Water offers a monthly credit for low-income customers who qualify for the California Alternate Rates for Water (CARW) program. Click here to learn more.

Cost of Capital and Rate of Return Application

Golden State Water Company has submitted its Cost of Capital application for 2018, 2019 and 2020. Click here to view the application and to view the service list, click here.

Click here to view the Cost of Capital 20-Day Notice.

Additional Resources/Rate Information:



Sample Forms

Service Lists