Backbone Transportation Service

Learn about Backbone Transportation Service and how to participate.

Important Dates

  • Current BTS contracts will end on September 30, 2026
  • New BTS contract period will commence October 1, 2026

Backbone Transportation Service (BTS) is applicable to firm and interruptible access to the SoCalGas® and San Diego Gas & Electric® (SDG&E®) integrated natural gas transmission system under Schedule No. G-BTS.  BTS participation requires a Master Services Contract (MSC), a Receipt Point Master Agreement (RPMA), an Electronic Bulletin Board (EBB) Agreement, and creditworthiness.

Participants may include any creditworthy party, wholesale customers, natural gas suppliers, and California Gas Producers.  Parties can electronically transact via SoCalGas ENVOY®, the SoCalGas EBB system, functions such as:

  •  Purchase firm and/or interruptible BTS rights electronically at receipt points into the SoCalGas and SDG&E integrated natural gas transmission system to transport natural gas onto or off the transmission system
  • Sell firm BTS rights through the secondary market trading module to other parties
  • Exchange Receipt Point BTS rights
  • Purchase and use off-system deliveries from the  SoCalGas and SDG&E integrated natural gas transmission system to all interstate and international pipelines, excluding California producer delivery points (See Rate Schedule No. G-OSD).
  • Utilize Citygate and Receipt Point Pooling Services (see Rate Schedule No. G-POOL)

Open Season

SoCalGas will hold an Open Season in the summer of 2026 in which parties may bid for firm rights for BTS service at the applicable tariff rates.

All current Schedule M Receipt Point Master Agreements (RPMA) and Schedule K Pooling Service Agreements (PSA) continue in effect.

Regulatory Background

Who Can Participate

The following parties are eligible to participate in the Backbone Transportation Service Open Season:

  • Non-core, end-use transportation customers of SoCalGas, SDG&E, Southwest Gas and City of Long Beach
  • Wholesale Customers of SoCalGas
  •  SoCalGas and SDG&E Gas Procurement Department
  • California Gas Producers
  • Contracted Marketers
  • Core  Transport Agents (CTAs)
  • Storage Customers
  • Any creditworthy party

New Participant Options for 2026

To Be Determined

Backbone Transportation Service Timeline (Dates Subject to Change)

To Be Determined


  • California Producer to BTSC (1)
  • California Producer to Receipt Point Pool (16)
  • Pipeline to BTSC (2)
  • Pipeline to Receipt Point Pool (18)

Receipt Point Pool

  • Receipt Point Pool (17)
  • Receipt Point Pool to BTSC (19)

Backbone Transportation Service Contract

  • BTSC to End User (3)
  • BTSC to City Gate Pool (4)
  • BTSC to Storage (5)

Off-System Delivery

  • OSD to Pipeline (14)

City Gate Pool

  • City Gate Pool to End User (6)
  • City Gate Pool to City Gate Pool (7)
  • City Gate Pool to Storage (9)
  • City Gate Pool to OSD (13)


  • Storage to End User (8)
  • Storage to City Gate Pool (10)
  • Storage to Storage (11)
  • Storage to OSD (12)

End User

  • End User to Storage (15)

Delivering Pipelines

  • CP Receipt Points
  • EPN – El Paso Natural Gas Pipeline
  • TGN – Transportadora de Gas Natural de Baja California
  • NBP – North Baja Pipeline
  • TW – Transwestern Pipeline
  • MP – Mojave Pipeline
  • KR – Kern River Pipeline
  • PG&E – Pacific Gas and Electric
  • OEHI – Occidental of Elk Hills

Customers holding firm BTS capacity will be able to nominate natural gas for delivery in accordance with SoCalGas' Rule No. 30 and SDG&E's Rule No. 30.

Off-System Delivery

SoCalGas will contract with any creditworthy party for Interruptible Off-System delivery under the G-OSD tariff. SoCalGas will make available physical displacement capacity at the receipt point on an interruptible basis at the applicable G-OSDI rate.

Pooling Service

Pooling is the administrative aggregation or disaggregation of natural gas supplies at the Citygate and receipt points and is defined in SoCalGas’ G-POOL tariff. Each customer may have a single pool contract where they will be able to nominate supplies coming through any Backbone Transportation Service Contract (BTSC) and nominate supplies out of the pool contract to end-users, other pool contracts, off-system, or to storage accounts. The Citygate and receipt point pool contract will be required to balance through each nominating cycle.

Agent Designation for Nominating and Trading Rights

A customer may opt to designate one and only one nominating agent or trading agent in addition to itself at any one time to nominate on all BTSCs under a customer’s RPMA. Customer must provide appropriate written authorization to SoCalGas of its intent to add or change a designated nominating or trading agent via the Nomination and Trading Authorization Form (Form No. 9924). Such designation shall be subject to that agent complying with applicable tariff and contractual provisions. Customer shall provide appropriate written notice to SoCalGas of its intent to terminate a nominating agent via the Termination of Nominating or Trading Agent Form (Form No. 9926).

Buying Backbone Transportation Service Rights

SoCalGas will provide eligible participants the opportunity to buy Backbone Transportation Service Rights before, during, and after the Open Season Process. Open Season step one and Open Season step two participants will receive an email with their maximum bidding rights based on historical usage and all necessary agreements. All participants will utilize the SoCalGas online bidding system for the Firm Receipt Points Access Rights during the Open Season Bidding process. After the Open Season is completed, customers will be able to buy rights via SoCalGas ENVOY.

Below are the available Open Season options. 

  • Buy Firm Rights in step one and two by accepting the set-asides or bidding rights provided by SoCalGas via the Open Season online bidding system.
  • Buy Firm Rights in step three via the online bidding system.
  • Re-contract your awarded rights by exchanging them to a different receipt point.

Open Season Process

The Open Season Process steps are available to eligible creditworthy participants. Participants must have a Master Services Contract, complete a Receipt Point Master Services Agreement (RPMA) and register through the online bidding system at the SoCalGas website. The online bidding website will be available only during the Open Season process.

Step One -- Open Season: Set-Aside Receipt Point Rights

Open Season step one of the Backbone Transportation Service bidding process will be reserved for the assignment option of set-aside capacity to specific customers as detailed in the G-BTS Backbone Transportation Service tariff including:

Step one participants: 

  • SoCalGas and SDG&E Gas Procurement Department
  • Utility Gas Procurement Department
  • Wholesale Customers excluding SDG&E
  • California Gas Producers
  • PG&E G-XF Contracts
  • Core Transport Agents (CTAs)
Step one details:
  • Rate Schedule G-BTS1 or G-BTS2
  • Term: three years
  • Preliminary set-asides

Step Two -- Open Season: Preferential Bidding

End-use customers in good credit standing with SoCalGas are deemed creditworthy to their specified maximum bidding rights. 

Step two participants:

  • Natural gas suppliers with customer assigned bidding rights1
  • Non-  core end-use transportation customers of SoCalGas and SDG&E
  • Non-core end-use transportation customers of wholesale customers
  •  SoCalGas and SDG&E Gas Procurement Department
  • Core Transport Agents (CTAs)
  • Parties with tolling agreements

 Step two details:

  • Three Rounds
  • Rate schedule G-BTS1 or G-BTS2
  • Term: three years
  • Maximum bidding rights provided to each participant

1Eligible end use customers may assign their Open Season bidding rights to a third party. The assignment of rights is for the entire volume and term. The form and additional details can be found at the Backbone Transportation Service Assignment Form section.

Step Three -- Open Season: Long Term

Step three participants:

  • Any creditworthy party may participate

Step three details:

  • One round
  • Rate schedule G-BTS1 or G-BTS2
  • Term: three to twenty years
  • Available capacity is any receipt point capacity remaining after the step two process
  • Bids are for annual base load only

Backbone Transportation Service Rights Assignment Form

The Backbone Transportation Service Assignment form is designed  to allow eligible participants with bidding rights in step two of the Open Season to assign those rights to a third party (“assignee”). This enables the assignee to bid in step two of the Open Season and be the contract holder of the Backbone Transportation Service rights. The maximum bidding rights would be irrevocably transferred (unless cancelled prior to the Open Season step two) to the other party and BTS rights awarded during step two of the Open Season would be held in the name of the assignee.

The assignment or transfer of rights is for the entire quantity and term and may not be divided between separate assignees.

The election form must be completed by the end-use customer to allow SoCalGas to prepare the contracts, verify credit, and complete other administrative duties necessary for parties to bid for firm receipt point access rights during the Open Season, step two.

If a participant would like to retain their own backbone transportation service rights, they must notify SoCalGas, in writing, at least 60 days prior to the beginning of step two. These notifications should be sent to the participant’s account executive.

How to Participate in the BTS Open Season Process

New participants to the BTS Open Season must first establish credit with SoCalGas. You may contact the SoCalGas credit department at 1-866-313-6622. Non-core end-use customers of SoCalGas and SDG&E are deemed creditworthy up to their maximum bidding rights and do not need to complete the application.

Current  RPMA holders should review their credit limit with SoCalGas credit department based on G-BTS rate schedules. Those who would like to make additional requests for credit and all other interested parties in the BTS Open Season must complete and return the Contract Request form (PDF).

Complete the Contract Request form and email to or mail to:

ATTENTION: Capacity Products Support
555 W. Fifth Street
Mail Location GT20C3
Los Angeles, California 90013-1010

Once the contract request form is reviewed by SoCalGas, a credit application will be sent to the requestor.