Invested in Arizona

2019 Arizona base rate adjustment request

Continuing our commitment to you.

On May 1, 2019, Southwest Gas Corporation (“SWG”) filed an application for a permanent gross revenue increase with the Arizona Corporation Commission (“ACC”). On October 24, 2019, the Company filed an amendment to its application, proposing a $93 million revenue increase.  After careful consideration of SWG’s filing and the positions of the other parties in the case, the ACC authorized an increase of approximately $37 million, effective January 1, 2021, per Decision No. 77850 (Docket No. G-01551A-19-0055).
The residential basic service charge remains $10.70 per month. As reflected in the Decision, the $37 million increase is equivalent to a monthly bill increase of $3.50 (or 9.68%) for an average residential customer using 24 therms. Actual bills may be higher or lower than this amount, depending on customer usage and other rate adjustments.
The approved rate adjustment:
  • Reflects approximately $733 million in rate base investments Southwest Gas has made since 2015 to ensure the continued safety and reliability of our system to best serve customers’ energy needs
  • Incorporates the benefits of tax reform in proposed rates
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This amounts to a $0.12 per-day increase on the average residential customer's bill.
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The adjustment increases the average residential customer's natural gas bill by $3.50 per month.
The average Arizona customer’s natural gas bill will remain approximately 28% lower than in 2007.
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When compared with other residential utilities, Arizona customers will continue to enjoy significantly lower natural gas bills.
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Frequently Asked Questions
How will this proposal affect my bill?
Under the proposed increase, we estimate that the average residential customer that uses 24 therms per month will experience an increase of approximately $3.50 a month.
When will I see this change on my bill?
Rates are effective January 1, 2021 , so you will see the change in the first billing cycle in 2021.
Why does Southwest Gas need to adjust my rates?
There are three primary reasons: to start recovering the costs associated with the increase in rate base of approximately $733 million since 2015; to update authorized revenues so that they reflect changes in the level of operating expenses since 2015; and to incorporate the benefits of tax reform in rates.
When was the last time Southwest Gas requested a base rate adjustment in Arizona?
In May 2016.
How much has Southwest Gas invested in its Arizona distribution system since the last rate case?
We have invested approximately $733 million in rate base in the Arizona gas distribution system since the last rate case.
Is Southwest Gas proposing changes to the components on my bill?
No, our proposal maintains the current rate design that’s been in place since January 2012. The proposed rate design will continue to include a monthly basic service charge and a volumetric rate — that captures both the delivery charge and gas cost component on your bill.
Is Southwest Gas proposing to change the basic service charge?
No, our proposal will not change the current basic service charge on your bill.
Why does Southwest Gas have various safety and reliability programs?
Just like a house needs maintenance and replacement work as it ages, all natural gas facilities require rigorous monitoring and maintenance, and ultimately replacement at some point. This ensures that the natural gas facilities continue to operate safely and reliably. We diligently plan these replacements in a systematic and deliberate manner which exceeds industry standards. In addition to the operational benefits, these programs help minimize the bill impacts to customers, as they result in smaller, more frequent rate adjustments over time.
What is Renewable Natural Gas (RNG)?
RNG is a biogas that is cleaned and upgraded to pipeline-quality gas and can be injected into and distributed through the Company’s distribution system. RNG is a carbon-neutral fuel that offers greater benefits when it is produced from organic waste that would otherwise decay and create methane emissions. There are many sources of biogas in Arizona, including wastewater treatment plants, dairies and landfills. Many wastewater treatment plants and landfills in Arizona capture biogas to prevent the direct release of the harmful greenhouse gas, methane, into the atmosphere. However, most Arizona biogas is not currently cleaned or upgraded to RNG and, therefore, is not capable of being injected into an existing natural gas delivery system.
What is the RNG Program?
Southwest Gas is proposing an RNG Program to develop Arizona RNG resources and keep the supply in Arizona to benefit the State. The Company’s proposal would allow the Company to meet up to 1% of its forecasted annual Arizona retail sales with RNG purchases by 2025, 2% by 2030 and 3% by 2035. The estimated cost of this program for residential customers is approximately $0.26/month for RNG purchases at 1% of forecasted annual Arizona retail sales.
Where can I get more information?
You can download a copy of our filing by clicking here

1Southwest Gas: Estimated Average Arizona Residential Bill

2U.S. Energy Information Administration (EIA): 2018 Arizona Electricity Data 

3Circle of Blue: 2018 Water Pricing - Phoenix (family of 4 using 150 gallons per person daily)

4NerdWallet: 2018 National Cell Phone Plan Comparison

5Fortune Media: 2018 National Cable and Satellite Bill