On September 21, 1977, the Company was incorporated as a limited company under the Civil and Commercial Code named “Siam United Services Co., Ltd.” with an authorized capital of Baht 5 million to render oil transportation services by tankers to the large oil traders at that time such as Esso (Thailand) Co., Ltd., The Shell Company of Thailand Ltd., and Caltex Oil (Thailand) Co., Ltd.

In 1985, the Company raised its paid-up capital from Baht 5 million to Baht 75 million, and on December 25, 1985, the Company was permitted by the Ministry of Commerce for fuel trading under Section 6 of the Fuel Oil Trading Act, B.E. 2521 (1978) and under Section 63 of the Fuel Oil Trading Act, B.E. 2543 (2000) which prescribed that, “The fuel trader as permitted by the Minister under Section 6 of the Fuel Oil Trading Act, B.E. 2521 (1978) is the fuel trader under Section 7 of this Act”; as a result, the Company which is a fuel trader under Section 7 of the said Act can also import fuel for domestic sale.

In 1986, the Company commenced to distribute fuels via the Company’s 32 petrol stations in the Southern Region. In the same year, the Company separated the fuel transportation business mentioned above from the fuel trading business by selling 6 fuel tankers and related assets to Siam Mongkol Marine Co., Ltd., its associated company. Subsequently, the Company expanded the number of its petrol stations almost throughout the regions.

On August 31, 1990, the Company became a listed company on The Stock Exchange of Thailand, having Baht 280 million paid-up capital, comprising 280 million common shares at the par value of Baht 10 each.

On February 8, 1993, the Company was converted to a public company limited, named “Siam United Services Public Co., Ltd.”

On November 26, 2010, the Extraordinary General Meeting No. 1/2553 resolved to change the name from “Siam United Services Public Co., Ltd.” to “SUSCO Public Co., Ltd.” and was certified by the Department of Business Development, Ministry of Commerce, to use the name “SUSCO Public Co., Ltd.” on December 15, 2010.

On November 16, 2012, the Extraordinary General Meeting No. 1/2555 passed a resolution approving the Company to acquire all shares in PETRONAS Retail (Thailand) Co., Ltd. and Universal Asset Co., Ltd. which traded fuels under “PETRONAS” trademark. The shares were acquired on December 3, 2012 and changed the names of the 5 PETRONAS companies to 1) SUSCO Dealers Co., Ltd., 2) SUSCO Retail Property Co., Ltd., 3) SUSCO Marketing Co., Ltd., 4) SUSCO Lubricants Co., Ltd., and 5) SUSCO Property Co., Ltd., and within 2014 would have to change the “PETRONAS” trademark to “SUSCO”.

On August 27, 2020, the Board of Directors’ Meeting No. 8/2563 approved the Share Repurchase Project for Financial Management purpose, in the maximum amount of Baht 180 million, being the number of shares to be repurchased not to exceed 55,000,000 shares or 5.00 percent of the total issued shares. At the end of the project, the Company repurchased a total of 50,000,100 shares or 4.55 percent of the total issued shares.

On September 30, 2020, The Company was recertified by Thailand's Private Sector Collective Action Coalition Against Corruption.

The Group of Companies has giving an importance to operate by taking into account the Environment, Social, and Governance. In 2021, the Board of Directors’ Meeting resolved to approve the sustainability policy framework and hired a consultant to collect carbon footprint data of the Company. In 2022, the Board of Directors set up the Corporate Governance and Sustainability Committee to oversee issues regarding the corporate governance for sustainability.

On September 29, 2022, the Board of Directors’ Meeting No. 9/2022 approved the reduction of repurchased capital totaling 50,005,500 shares or 4.55 % of current paid-up capital.

On October 27, 2022, the Board of Directors’ Meeting No. 10/2022 resolved to establish a new subsidiary, “SUSCO Beyond Co., Ltd.” to expand new potential business of which the registered capital is 100,000,000 Baht and 100 % of shares owned by the Company.

On February 28, 2023, The Extraordinary General Meeting of Shareholders No. 1/2023 resolved to sell 45,863,430 ordinary shares and 955,488 preferred shares of SUSCO Dealers Co, Ltd. to Sinopec (Hong Kong) Limited, resulting in a change in status from a subsidiary to a joint venture which later changed the name to “SINOPEC SUSCO Co., Ltd.”.

On April 26, 2023, the Board of Directors’ Meeting No. 5/2023 of SUSCO Beyond Co, Ltd. a subsidiary of the Company resolved to approved the joint investment in the battery exchange station and electric motorcycle rental project along with a maintenance center in Koh Samui, Surat Thani with AMR Asia Public Co, Ltd. by establishing an associate company under the name "AS MaCharge Co, Ltd." with an investment proportion of 40 % of the investment value.

On July 25, 2023, the Board of Directors’ Meeting No. 7/2023 resolved to approve the purchase of the newly issued ordinary shares and the ordinary shares of Siam Mongkol Marine Co, Ltd. from its shareholders and connected persons in an amount not exceeding 4,010,637 shares which made the Company holding shares in excess of 50 % of the registered capital of such associated company, thus Siam Mongkol Marine Co., Ltd. has changed its status to a subsidiary of the Company.

On September 30, 2023, the Company was recertified by Thailand’s Private Sector Collective Action Coalition Against Corruption.

As of December 31, 2023, the Company owned 3 oil depots, namely: Ratburana Oil Depot, Surat Thani Oil Depot, and Songkhla Oil Depot, and also had many joint oil depots to store fuels purchased by the Company from various sources for sale and legal reserve. The Company and its subsidiaries had a total of 262 petrol stations scattered almost throughout the country; 227 stations were operated by the Company and 35 stations were operated by dealers. In addition, SUSCO Beyond Co.Ltd., the subsidiary of the Company, owned 7 electric car showrooms and services, namely; Pratunam Phra-in branch, Ang Thong branch, Rama 2 branch, Rama 9 branch, Central Westgate branch, Central Pinklao branch and Vibhavadi 62 branch.

On March 15, 2024, the Company received a certificate of accreditation for greenhouse gas emissions assessment and reporting according to ISO 14064-1: 2018 from Bureau Veritas Certification (Thailand) Co., Ltd. to certify that SUSCO is an organization that has been certified for the assessment of "Carbon Footprint for Organization: CFO" that conducts business with environmental concern, social responsibility, and sustainability in mind, leading to a plan to reduce greenhouse gas emissions. The assessment was based on greenhouse gas emissions from the Company's operations and activities throughout the year. The Company has upgraded its environmental management to achieve Net Zero Greenhouse Gas Emissions in the future, setting a target to achieve Carbon Neutrality by 2060 and Net Zero by 2073.

On May 13, 2024, SUSCO Beyond Company Limited (a subsidiary of the Company), together with IFS Capital (Thailand) Company Limited (Public Company), a specialist in the credit business and a leader in the factoring business that has been serving SMEs for over 30 years, signed a joint venture agreement under the name Beyond Leasing Company Limited to operate a business as a provider of financial lease agreements, capital lease agreements, hire purchase agreements, and related financial services for customers who want to lease cars. It also supports the expansion into other financial services businesses in the future.

On May 31, 2024, SINOPEC SUSCO Company Limited (a joint venture of the Company) officially operates a gas station business in Thailand under the brand SINOPEC SUSCO. It has expanded its business by opening the first "EASY JOY" Chinese convenience store in Thailand at SINOPEC SUSCO gas station, Thap Chang branch, on the Suvarnabhumi Airport Expressway.

On June 5, 2024, the Company signed a Memorandum of Understanding (MOU) for cooperation in the "Standard Fuel Dispenser" project with the Department of Internal Trade, Ministry of Commerce. This collaboration project aims to assure consumers when using services at SUSCO gas stations that the fuel volume measurement from the fuel dispensers at the stations complies with legal requirements.

On September 16, 2024, the Company entered into a partnership with the Grab EV project, driven by Grab Thailand, in the "Drive to Own" program, which will enable Grab driver-partners to switch to electric vehicles more easily. The Company supports the hire purchase of BYD Seal vehicles with daily installments deducted from daily service revenue over a period of 5 years, with no down payment required. They are also entitled to other benefits to promote the use of electric vehicles (EVs) among Grab driver-partners, focusing on sustainability and reducing carbon dioxide emissions.

On October 30, 2024, the Company received an honorary award in the Thai capital market, the SET Awards 2024, in the Business Excellence category, namely the Outstanding CEO Awards, presented to Mr. Chairat Simaroj, Chief Executive Officer and Managing Director, as an outstanding executive in listed companies on the Stock Exchange of Thailand. The Company also received the Outstanding Company Performance Awards for companies with outstanding performance and a market capitalization of more than Baht 3,000 million but not more than Baht 10,000 million. The SET Awards 2024 Outstanding CEO Awards and Outstanding Company Performance Awards are organized by the Stock Exchange of Thailand (SET) in collaboration with Money & Banking Magazine to honor and recognize companies that excel in both business potential and sustainability, especially in conducting business amidst the rapidly changing challenges of today's world. This recognition aims to establish role models for various business sectors in developing organizational quality, creating innovation, achieving good operating results, and operating responsibly towards stakeholders, taking into account the environment, society, and corporate governance, leading to sustainable growth.

On December 10, 2024, SUSCO Beyond Company Limited (a subsidiary of the Company) officially launched the DENZA SUSCO Beyond Infinite showroom, Sathu Pradit branch. It is currently the largest DENZA showroom in Thailand, launching the first luxury electric car, DENZA D9, to meet the needs of consumers in the era of clean energy use, reflecting the commitment to being an industry leader and meeting the needs of modern consumers in a comprehensive manner.

In 2024, the Company collaborated with Bangchak Sriracha Public Company Limited to revamp the "Bangchak" gas stations under the management of "SUSCO" in the Northeast, North, and West, totaling 108 stations. There are also plans to develop cooperation in other areas such as Non-oil business, Bangchak Green Miles points accumulation, FURIO engine oil sales, etc., and aims to expand joint stations in this format in the future.

As of December 31, 2024, the Company had 3 oil depots owned by the Company, namely Rat Burana Oil Depot, Surat Thani Oil Depot, and Songkhla Oil Depot. In addition, there are several oil depots jointly owned with other companies to store oil that the group has purchased from various sources for resale and reserve in accordance with the law. The Group has a total of 240 gas stations located throughout the country. Of these, 211 are operated by the Company itself, selling fuel, natural gas (NGV), and liquefied petroleum gas (LPG), while 29 are leased to dealers. In addition, SUSCO Beyond Company Limited, a subsidiary of the Company, has 11 electric vehicle sales and service centers, namely, Pratunam Phra In Branch, Ang Thong Branch, Rama 2 Branch, Rama 9 Branch, Central WestGate Branch, Pinklao Branch, Vibhavadi 62 Branch, Ayutthaya Branch, Pracha Uthit Branch, Charansanitwong 83 Branch, and Sathu Pradit Branch.