Gas Transmission Northwest

TSP Name: Gas Transmission Northwest LLC
Notice ID: 1615
TSP: 006912885
Notice Type: Plnd Outage
Notice Status: Supersede
Posting Date/Time: 08/11/2026 15:50
Notice Eff Date: 08/11/2026
Notice Eff Time: 15:50
Notice End Date: 11/01/2026
Notice End Time: 08:59
Critical: Yes
Required Response: No response required
Prior Notice ID: 1612

Subject: MAINTENANCE SCHEDULE for Gas Transmission Northwest (Posted: 8/11/26)

Message Text:
Gas Transmission Northwest Maintenance Schedule has been updated. Please refer to the maintenance schedule for the projected capacity impacts. Updated items are as follows: • Removed: 8/11 – 8/27 – Bonanza Bypass Installation • Removed: 8/28 – 8/31 – Malin Receiver Installation Please note that the information posted is proposed and subject to change. Please direct any questions to your Account Coordinator, Customer Service Representative, or the Nominations and Scheduling hotline @ 888-750-6275

Attachments: GTN Planned Maintenance Schedule 20260811.pdf

TSP Name: Gas Transmission Northwest LLC
Notice ID: 1614
TSP: 006912885
Notice Type: Maint
Notice Status: Initiate
Posting Date/Time: 08/11/2026 10:00
Notice Eff Date: 08/11/2026
Notice Eff Time: 10:00
Notice End Date: 08/12/2026
Notice End Time: 08:59
Critical: Yes
Required Response: No response required

Subject: UPDATED: CAPACITY REDUCTION: GTN – Station 6 CFTP (Updated: 8/11/26)

Message Text:
Effective for Gas Day 8/12 Timely Cycle, GTN has completed the Rosalia Launcher Installation and Loading Valve Replacement. Capacity at Station 6 CFTP (LOC #954690) is being reinstated to 2,673 MMcf/d. Please note this does not supersede any other planned maintenance, refer to the posted maintenance schedule for additional impacts. Please direct any questions to your Account Coordinator, Customer Service Representative, or the Nominations and Scheduling hotline @ 888-750-6275

TSP Name: Gas Transmission Northwest LLC
Notice ID: 1608
TSP: 006912885
Notice Type: OFO
Notice Status: Initiate
Posting Date/Time: 08/01/2026 17:50
Notice Eff Date: 08/01/2026
Notice Eff Time: 17:50
Notice End Date: 09/01/2026
Notice End Time: 08:59
Critical: Yes
Required Response: No response required

Subject: OFO Watch: GTN Low Inventory (Posted 8/1/26)

Message Text:
Effective immediately, Gas Transmission Northwest (GTN) is issuing an OFO Watch due to low system inventory. GTN is concerned that continued low inventory levels may impact the operational integrity of its system. As a result, customers may experience lower-than-normal system pressures. This OFO Watch will remain in effect until further notice to allow GTN to maintain the operational integrity of its system. GTN currently has limited flexibility to manage imbalances and strongly encourages all shippers to closely manage their system requirements and maintain a daily balance between receipts and deliveries. Absent voluntary actions by shippers to maintain daily balance, GTN may be required to take additional measures, including the immediate issuance of an Operational Flow Order (OFO). Should further action become necessary, such action may be implemented immediately and without additional advance notice. This posting will be updated as additional information becomes available. Please direct any questions to your Account Coordinator, Customer Service Representative, or the Nominations and Scheduling Hotline at 888-750-6275.

TSP Name: Gas Transmission Northwest LLC
Notice ID: 1610
TSP: 006912885
Notice Type: TSP Cap Offer
Notice Status: Initiate
Posting Date/Time: 08/06/2026 08:44
Notice Eff Date: 08/06/2026
Notice Eff Time: 12:00
Notice End Date: 08/31/2026
Notice End Time: 12:00
Critical: No
Required Response: No response required
Response Date/Time: 08/11/2026 12:00

Subject: GTN Open Season for Sep 2026 capacity closes at 12:00 PM CT on August 11, 2026

Message Text:
GTN is posting an Open Season for September 2026 Kingsgate to Malin and September 2026 Turquoise Flats to Kingsgate MC This Open Season Closes at 12:00 PM CT on Tuesday August 11, 2026 Questions can be directed to: Sean McDonald 832-320-5332 Dan Junek 832-320-5825 Devan Mody 832-320-5951 Kirsten Kahanek 832-320-6746

Attachments: GTN Open Season September 2026 King-Malin and September 2026 Turquoise Flats to Kingsgate MC.docx

TSP Name: Gas Transmission Northwest LLC
Notice ID: 1603
TSP: 006912885
Notice Type: Rates-Chrgs
Notice Status: Initiate
Posting Date/Time: 07/18/2026 06:00
Notice Eff Date: 07/18/2026
Notice Eff Time: 06:00
Notice End Date: 08/31/2026
Notice End Time: 12:59
Critical: No
Required Response: No response required

Subject: AUGUST 2026 - GTN Fuel and Line Loss Percentage

Message Text:
Pursuant to Gas Transmission Northwest's (GTN) Tariffed Fuel Adjustments Provision, for the period of August 01, 2026 through August 31, 2026, a fuel usage rate of 0.0050% per Dth/mile will be in effect. This percentage is inclusive of GTN's current fuel and line loss surcharge of 0.00000% per Dth per pipeline mile, which is in effect through December 31, 2026, in accordance with GTN's approved tariff provision, "Adjustment Mechanism for Fuel, Line Loss, and Other Unaccounted for Gas." This posting is accompanied by the following attachments: GTN System Fuel Rates GTN Fuel and Line Loss Surcharge Historical GTN Fuel Rates (2012 to Present) If you have any questions, please contact Commercial Services at 888.750.6275

Attachments: GTN Fuel 08.2026.pdf Fuel and Line Loss Surcharge 2026.pdf GTN Historical Fuel Tracker 08.2026.pdf

TSP Name: Gas Transmission Northwest LLC
Notice ID: 1571
TSP: 006912885
Notice Type: Rates-Chrgs
Notice Status: Initiate
Posting Date/Time: 05/14/2026 12:10
Notice Eff Date: 05/14/2026
Notice Eff Time: 12:30
Notice End Date: 05/15/2027
Notice End Time: 23:59
Critical: No
Required Response: No response required

Subject: Rate Summary, Effective June 1, 2026

Message Text:
GTN rate summary of current rates effective June 1, 2026 through May 31, 2027. The rates are based upon an election of zero (0) peak months.

Attachments: GTN_2026_06_01.pdf

TSP Name: Gas Transmission Northwest LLC
Notice ID: 466
TSP: 006912885
Notice Type: Cap Rel
Notice Status: Initiate
Posting Date/Time: 05/24/2019 14:50
Notice Eff Date: 05/24/2019
Notice Eff Time: 14:55
Notice End Date: 12/31/2030
Notice End Time: 08:00
Critical: No
Required Response: No response required

Subject: Supported Price Index Reference

Message Text:
In reference to NAESB Standard 5.3.65, Gas Transmission Northwest LLC currently subscribes to Platts Gas Daily and Natural Gas Intelligence price indices. These subscriptions are renewed yearly.

TSP Name: Gas Transmission Northwest LLC
Notice ID: 113
TSP: 006912885
Notice Type: Cred Contacts
Notice Status: Initiate
Posting Date/Time: 07/29/2016 06:35
Notice Eff Date: 07/29/2016
Notice Eff Time: 06:36
Notice End Date: 12/31/2049
Notice End Time: 23:59
Critical: No
Required Response: No response required

Subject: Credit Contacts/Credit Forms

Message Text:
Attn: GTN Customers Re: Credit Contacts/Credit Forms Attached to this notice are copies of the most updated versions of the Guaranty and Letter of Credit. For additional Information, please contact: Credit Assessments/Financial Assurances Rita Homan Rita_homan@transcanada.com 832-320-5449 New Credit Requests Usman Kahn (primary) Usman_khan@transcanada.com 832-320-5418 Bridgett Bolden (back-up) Bridgett_bolden@transcanada.com 832-320-5230

Attachments: GTN LLC - LC Template-2016-07-14.docx GTN LLC Gty_Held_Master_August 2011.pdf