UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, DC 20549 _____________ FORM 6-K Report of Foreign Issuer Pursuant to Rule 13a-16 or 15d-16 of the Securities and Exchange Act of 1934 For March 25, 2026 Commission file number: 1-13.396 Transportadora de Gas del Sur S.A. Cecilia Grierson 355, Twenty sixth Floor (1107), Capital Federal Argentina Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F. Form 20-F X Form 40-F Indicate by ch ...

Core Insights - TGS, a leading global provider of energy data and intelligence, published its 2025 Annual Report and Management Remuneration Report on March 20, 2026 [1][2] Group 1: Company Overview - TGS provides advanced data and intelligence to companies in the energy sector, utilizing leading-edge technology and solutions across the entire energy value chain [2] - The company offers a comprehensive range of insights to assist clients in making informed decisions, supported by a diverse energy data library [2] Group 2: Report Availability - The Annual Report is available in the European Single Electronic Format (ESEF) and can be downloaded from the TGS website or Newsweb [2] - For further inquiries, contact information for Bård Stenberg, VP IR & Business Intelligence, is provided [2]

Core Points - On 1 March 2026, 15,000 Restricted Share Units (RSUs) granted to Carel Hooijkaas on 1 March 2023 vested according to the employment agreement and TGS Remuneration Policy [1][2] - Each vested RSU entitles the holder to receive one share of the Company's common stock, with 12,534 shares delivered from the treasury stock [2] - After the transaction, Carel Hooijkaas owns a total of 65,698 shares in TGS, while the number of treasury shares in TGS stands at 114,409 [3] Company Overview - TGS provides advanced data and intelligence to companies in the energy sector, utilizing leading-edge technology and solutions across the entire energy value chain [4] - The company offers a comprehensive range of insights to assist clients in making informed decisions, supported by a diverse energy data library [4]

Group 1 - TGS has announced a new acquisition campaign for the Ramform Vanguard, set to begin in mid-March, focusing on an oil and gas site survey followed by two offshore wind contracts, extending activities into the third quarter [1] - CEO Kristian Johansen expressed satisfaction with the acquisition campaign, highlighting potential for further work in the market and the possibility of extending the campaign towards the end of Q3 [2] - TGS aims to broaden its product offering by conducting its first oil and gas site survey, leveraging its Ultra High Resolution 3D streamer solution, which has a proven track record in offshore wind site characterization [2] Group 2 - TGS provides advanced data and intelligence to the energy sector, offering a comprehensive range of insights to support exploration and production of energy resources worldwide [3] - The company utilizes leading-edge technology and solutions that span the entire energy value chain, making it a trusted partner for clients in the industry [3]

Transportadora de Gas del Sur S.A. (NYSE:TGS) Q4 2025 Earnings call March 02, 2026 09:00 AM ET Company ParticipantsAlejandro Basso - CFOOperatorBefore we begin the call, I would like to inform you that this event is being recorded and all participants are in listen-only mode. Following the company remarks, we will host a Q&A session. All question will need to be submitted in writing through the Q&A chat box. I would also like to remind you that forward-looking statement made during today's video conference ...

Financial Data and Key Metrics Changes - The total net income for Q4 2025 was ARS 124 billion, down from ARS 170.5 billion in Q4 2024, primarily due to the reversal of a property plant and equipment impairment provision of ARS 52.1 billion recorded in Q4 2024 [4] - EBITDA for natural gas transportation increased slightly to ARS 109.8 billion in Q4 2025 from ARS 107.1 billion in Q4 2024, despite an inflation loss effect of ARS 40.9 billion [5][6] - Liquids segment EBITDA decreased to ARS 83.9 billion in Q4 2025 from ARS 102 billion in Q4 2024, attributed to lower export prices and increased operating costs [6][8] Business Line Data and Key Metrics Changes - The midstream business delivered higher EBITDA of ARS 16.2 billion, contributing positively to overall performance [5] - Liquids segment EBITDA was negatively impacted by lower export prices, which fell between 17% and 33%, and higher operating costs [6][8] - EBITDA from midstream and other services rose by 36% to ARS 60.7 billion, driven by increased natural gas transportation and conditioning volumes [9] Market Data and Key Metrics Changes - The average natural gas price remained stable at $1.6 per million BTU year-over-year, which is a key variable cost for the liquids business segment [8] - The company experienced a negative variation in financial results amounting to ARS 17.9 billion, primarily due to higher interest costs and lower yields from financial assets [10] Company Strategy and Development Direction - The company successfully issued a $500 million bond to fund approximately $780 million of CapEx for the expansion of the Perito Moreno pipeline, which will add significant transportation capacity [2] - The company is negotiating terms with gas producers for the NGL project, expecting to reach the Final Investment Decision (FID) by May or June [15] - The company plans to invest heavily in the expansion project, with a total CapEx of around $780 million, primarily allocated for 2026 [29][30] Management's Comments on Operating Environment and Future Outlook - Management noted that tariff adjustments in the transportation business are moving smoothly, with adjustments based on inflation calculations [19] - The outlook for liquids prices remains stable, with no significant changes expected despite recent geopolitical conflicts that may positively affect the segment [22][24] - Management expressed confidence in gas supply for the NGL project, indicating that they may face higher supply than expected [32] Other Important Information - The cash position increased significantly to ARS 1,808 billion, equivalent to approximately $1.25 billion, primarily due to the bond issuance [12] - The company recorded a negative variation in financial results due to higher interest costs and lower yields from financial assets [10] Q&A Session Summary Question: Update on the NGL project and potential delays for FID - The project is progressing well, with negotiations ongoing, and FID expected before June [15] Question: Competition from YPF in shale capabilities - Competition is acknowledged as a risk, but the company is working with YPF and other gas producers [17][18] Question: Evolution of tariffs in the transportation business - Tariff adjustments are proceeding smoothly, with inflation-based calculations in place [19] Question: Status of Surrey insurance reimbursement - Advance payments of almost $10 million have been collected, with final audit expected soon [21] Question: Outlook for liquid pricing into 2026 - Current outlook for liquids prices is stable, with potential positive effects from geopolitical conflicts [22][24] Question: Potential dividend payments in 2026 - No potential dividend payments are anticipated as the company focuses on project development [27] Question: CapEx allocation for expansion projects - Total CapEx for the expansion project is around $780 million, with significant investment planned for 2026 [29][30] Question: Progress on Perito Moreno expansion and expected CapEx - Progress is on track, with expected CapEx of around $100 million in 2025 and over $500 million in 2026 [33]

Financial Data and Key Metrics Changes - The total net income for Q4 2025 was ARS 124 billion, a decrease from ARS 170.5 billion in Q4 2024, primarily due to the reversal of a property plant and equipment impairment provision of ARS 52.1 billion recorded in Q4 2024 [4] - EBITDA for natural gas transportation increased slightly to ARS 109.8 billion from ARS 107.1 billion year-over-year, despite an inflation loss effect of ARS 40.9 billion [5][6] - Liquids segment EBITDA decreased to ARS 83.9 billion from ARS 102 billion, attributed to lower export prices and increased operating costs [6][7] Business Line Data and Key Metrics Changes - The midstream business delivered higher EBITDA of ARS 16.2 billion, contributing positively to overall performance [5] - Liquids segment EBITDA was negatively impacted by lower export prices, which fell between 17% and 33%, and higher operating costs [6][7] - EBITDA from midstream and other services rose by 36% to ARS 60.7 billion, driven by increased natural gas volumes transported and conditioned [8] Market Data and Key Metrics Changes - The average natural gas price remained stable at $1.6 per million BTU year-over-year, impacting the liquids business segment [7] - The company experienced a negative variation in financial results amounting to ARS 17.9 billion, primarily due to higher interest costs and decreased income from financial assets [9] Company Strategy and Development Direction - The company successfully issued a $500 million bond to fund approximately $780 million of CapEx for the expansion of the Perito Moreno pipeline, which will add significant transportation capacity [2] - The company is negotiating terms with gas producers for the NGL project, expecting to reach the Final Investment Decision (FID) by May or June [14] - The company plans to invest heavily in the expansion project, with a total CapEx of around $780 million allocated for 2026 [26][32] Management's Comments on Operating Environment and Future Outlook - Management noted that tariff adjustments in the transportation business are moving smoothly, with adjustments based on inflation calculations [18] - The outlook for liquids prices is expected to remain stable, with potential positive impacts from current geopolitical conflicts [21] - Management expressed confidence in gas supply for the NGL project, anticipating higher supply than expected [31] Other Important Information - The cash position increased significantly to ARS 1,808 billion, equivalent to approximately $1.25 billion, primarily due to the bond issuance [10] - The company recorded a significant increase in cash flow generation, with nearly ARS 259 billion in EBITDA for Q4 [11] Q&A Session Summary Question: Update on the NGL project and potential delays for FID - Management confirmed that negotiations with gas producers are ongoing and expects to reach FID by May [14] Question: Competition from YPF in shale capabilities - Management acknowledged competition but emphasized ongoing collaboration with YPF and other gas producers [16] Question: Evolution of tariffs in the transportation business - Management stated that tariff adjustments are proceeding as planned, based on inflation calculations [18] Question: Status of insurance reimbursement from the Surrey incident - Management reported advance payments of almost $10 million received and expects final audit results by June or July [20] Question: Outlook for liquid pricing into 2026 amid international energy price weakness - Management indicated that while international NGL prices are currently weak, margins remain good, and geopolitical conflicts may positively affect pricing [21] Question: Potential dividend payments in 2026 - Management does not foresee potential dividend payments as focus remains on project development [25] Question: CapEx allocation for the expansion project - Management confirmed that total CapEx for the expansion project is around $780 million, with significant investments planned for 2026 [26][32] Question: Progress on the Perito Moreno expansion and expected CapEx for 2026 and 2027 - Management reported that progress is on track, with expected CapEx of around $100 million in 2025 and over $500 million in 2026 [32]

Core Insights - TGS announces the Nigeria Laide multi-client 3D survey in collaboration with NUPRC and SeaSeis Geophysical, covering approximately 11,700 square kilometers in the eastern Niger Delta, a significant hydrocarbon region [1][3] Technology and Methodology - The survey utilizes the GeoStreamer dual-sensor system with long offsets, wide tow, and a triple-source configuration, providing modern broadband seismic data that enhances the evaluation of complex geological structures in the deepwater eastern Niger Delta [2] - Advanced Elastic FWI-driven velocity model building supports full-integrity PSTM and Q-PSDM, enabling operators to address geological challenges such as stacked toe-thrust structures and shale diapirs [2] Strategic Importance - The CEO of TGS emphasizes Nigeria's critical role in the global oil and gas supply, highlighting the company's commitment to hydrocarbon exploration in the region through the Laide 3D survey [3] - The survey is backed by industry funding, indicating strong market interest and support for exploration activities in Nigeria [3]

OSLO, NORWAY (19 February 2026) – The shares in TGS ASA will be traded ex dividend NOK 1.47 (USD 0.155) as from today, 19 February 2026. ...

Financial Performance - TGS reported Q4 2025 revenues of USD 363 million, driven by strong multi-client performance with a sales-to-investment ratio of 2.0x for the full year 2025 [5] - The company achieved an order inflow of USD 598 million in Q4 2025, marking the best quarter since before the pandemic, and increased total order backlog to USD 706 million [5] - TGS generated a net cash flow before dividends of over USD 200 million and reduced net debt to USD 427 million by year-end, despite challenging market conditions [2][5] Strategic Insights - The Imaging division experienced a 65% growth in pro-forma external revenue for 2025, attributed to a sharpened strategic approach [1] - The company maintained a focus on cost and capital efficiency, leading to a substantial reduction in costs [2] - Management anticipates a sustained recovery in demand as the global oil market is expected to move toward a more balanced state in the latter part of 2026 [3] Future Guidance - For 2026, TGS plans to invest in multi-client projects in the range of USD 500-575 million, an increase from USD 447 million in 2025, supported by strong customer commitments [5] - The company expects significant increases in vessel utilization driven by high multi-client activity, with OBN activity anticipated to be in line with 2025 [5] - Gross operating costs are projected to be approximately USD 950 million, with capital expenditures expected to remain at similar levels as in 2025 [5]