Global pressure on corporations to provide transparent climate and sustainability disclosures is reshaping reporting standards across capital markets. Anticipating that shift, MTN released its first sustainability report in 2018. And it has just published its 2025 Sustainability Report in compliance with International Financial Reporting Standards (IFRS) S1 and S2. It is one of the few African-listed companies to voluntarily adopt the framework ahead of its mandatory implementation timeline.

MTN Nigeria

The report marks MTN Nigeria’s seventh consecutive annual sustainability publication and third straight year as an early adopter of the IFRS sustainability disclosure standards. Independently assured by Ernst & Young (EY), the report aligns with multiple global and local reporting frameworks, including the Global Reporting Initiative Standards, the Sustainability Accounting Standards Board telecommunications standard, the UN Global Compact Principles, the Nigerian Exchange sustainability guidelines, and the Securities and Exchange Commission’s Sustainable Finance Principles.

MTN Nigeria’s CEO, Dr. Karl Toriola, said: “Strong governance and ethical conduct are foundational to our sustainability strategy. We reinforced compliance through our Conduct Passport Framework and robust internal controls.”

In May 2025, we became the first telecommunications company in Nigeria to publicly present a sustainability report on the Nigerian Exchange Group platform, an important milestone in our commitment to IFRS S1 and S2- aligned disclosure and accountability.”

The company also secured Carbon Disclosure Project ratings of ‘B-’ for climate change and ‘C’ for water security. Under the IFRS S2 framework, the telecoms operator disclosed climate-related risks linked to flooding, heat stress, regulatory changes and possible future taxes or charges on carbon emissions, following a climate scenario analysis completed in 2024.

The report also showed that MTN Nigeria now uses a digital reporting format – XBRL. This makes its sustainability and governance data easier for investors and ESG rating agencies to access and analyse through automated systems.

They also carried out assessments to understand how sustainability issues affect both its business operations and society at large, while measuring its overall economic, environmental and social impact from 2021 to 2024.

In addition, over one-third of MTN Nigeria’s biggest suppliers (based on spending) have committed to supporting the company’s net-zero emissions goals, although these commitments have not yet gone through an independent audit or verification process.

The top ten mobile network operators in the world account for roughly 3.8 billion subscriptions, about 43 percent of the 8.8 billion mobile lines in service worldwide as of mid-2024.

The composition of that top ten has changed substantially over the past decade.

China Mobile crossed one billion subscribers in the second quarter of 2024 and remains in first place by a wide margin.

Reliance Jio, which did not exist before September 2016, is now the world’s second-largest mobile operator and a clear example of how quickly the rankings have moved.

Vodafone Group, long counted second worldwide, has divested operations in India, Italy, Spain, and Australia since 2019 and now sits well outside the top five.

This article runs through the major operators with current subscriber figures, then closes with a fifteen-country table and a short note on what has changed since the industry’s last reshuffle.

China Mobile

China Mobile reached 1.004 billion subscribers in the second quarter of 2024, the first single operator anywhere to pass the one-billion line.

It accounts for roughly 19 percent of all global mobile subscriptions on its own.

The company was carved out of the original China Telecom in 1999 and listed on both the Hong Kong and New York stock exchanges, though it remains majority-owned by the Chinese state.

Growth has slowed sharply as the Chinese market has saturated: China Mobile took until Q4 2014 to reach 800 million subscribers and nearly another full decade to add the next 200 million.

Its 5G subscriber base reached 599 million by the end of 2025, by far the largest 5G network in the world.

In revenue terms China Mobile reported roughly 98.4 billion euros in 2024, comparable to Deutsche Telekom but well below Verizon and AT&T.

Reliance Jio

Reliance Jio launched commercial 4G service across India in September 2016 with an aggressive bundled-data pricing strategy that effectively ended the previous Indian market structure.

Subscriber numbers reached 481.8 million by mid-2024, ranking Jio second worldwide and the largest single-country operator outside China.

Jio is a subsidiary of Reliance Industries, the conglomerate founded by Dhirubhai Ambani and now led by his son Mukesh Ambani; the unit’s data plans in 2025 included tiers as low as roughly US$2.17 for three gigabytes of data, with cricket-season offers pushing that to 15 gigabytes for US$2.73 on a 90-day validity. The combination of low ARPU and very high subscriber volumes is now the standard story across Indian telecoms, and Jio is the operator that set it.

China Telecom

China Telecom, the parent of the 1999 break-up that produced China Mobile, ranks third globally with 422.67 million mobile subscribers in 2024.

Like China Mobile and China Unicom, it is a state-owned enterprise headquartered in Beijing and listed in both Hong Kong and (until 2021) New York.

China Telecom historically held the largest share of the Chinese fixed-line market and entered mobile services later than China Mobile; its mobile business has grown steadily through the 5G transition, with 5G handset subscribers crossing 350 million in 2024.

Bharti Airtel

Bharti Airtel, headquartered at Bharti Crescent in New Delhi, ranked fourth in 2024 with 395.15 million subscribers across India, Sri Lanka, and fourteen African countries.

The company was founded by Sunil Bharti Mittal as Bharti Telecom in 1995, with the Airtel brand launched the same year for mobile service in Delhi. Airtel’s African operations are run through Airtel Africa, listed separately on the London Stock Exchange since 2019, and account for roughly a third of total group subscribers.

Airtel posted the strongest revenue growth of any of the world’s top twenty telcos in the year to Q3 2024 (4.6 percent), driven by ARPU gains in both India and several large African markets.

China Unicom

China Unicom, the third state-owned Chinese carrier, ranked fifth globally in 2024 with 339.3 million mobile subscribers.

The company was created in 1994 to break China Telecom’s then-monopoly on telecommunications services, and it remains the smallest of the three Chinese state operators by mobile market share. China Unicom merged its mobile and fixed-line networks with China Telecom for 5G deployment in 2019, sharing infrastructure to reduce build costs across the country’s vast rural areas.

The Global Multinationals

América Móvil, headquartered in Mexico City and controlled by the family of Carlos Slim, served 323 million mobile subscribers as of 2024, anchored by Telcel in Mexico (the dominant national operator) and Claro brand operations across most of Latin America. Telefónica, headquartered in Madrid, served roughly 300 million across Spain, Brazil (under the Vivo brand), Germany, the United Kingdom, and several other markets, though it has been divesting non-core operations and the global subscriber number has trended down.

Orange, the former France Télécom rebranded in 2013, served 253 million across France, Spain, Belgium, Poland, and twenty-plus African and Middle Eastern markets through its Orange Middle East and Africa subsidiary. MTN Group, headquartered in Johannesburg, served roughly 290 million subscribers across 21 African countries (with Nigeria and South Africa as its two largest markets), making it the largest African operator and the eighth-largest worldwide.

Vodafone Group

The Shard in London, with the wider city skyline of the United Kingdom in the background.

The Shard, London. Vodafone Group is headquartered in the United Kingdom.

Vodafone Group is no longer the world’s second-largest mobile operator.

The company has spent the past six years divesting from markets where it was unable to lead: it sold Vodafone India to merge with Idea Cellular in 2018 (creating the standalone Indian operator Vodafone Idea, in which Vodafone Group retains a 23.2 percent stake); sold Vodafone Italy to Swisscom; sold Vodafone Spain to Zegona Communications in 2023; exited Australia through a merger; and in 2025 merged Vodafone UK with Three UK to create the largest mobile operator in the British market.

The remaining Vodafone Group footprint is concentrated in Germany, the UK (post-Three merger), and African markets where it operates through Vodacom.

Total Vodafone Group mobile subscribers, including Vodacom but excluding the minority-held Vodafone Idea stake, sit in the 270 to 300 million range depending on which businesses are counted in or out, well below the 469.7 million figure that placed Vodafone second worldwide a decade ago.

MTN Nigeria has cut its greenhouse gas emissions by 6.4 per cent even as it estimates that powering its nationwide network with diesel costs more than N60 billion every year.

In its newly released 2025 Sustainability Report, the telecom operator said its operational emissions fell by 6.4%, driven by investments in cleaner and more efficient energy solutions.

The company’s climate efforts are anchored on Project Zero, MTN’s long-term strategy to achieve net-zero emissions by 2040.

In 2025, the telco invested N10.1 billion in the initiative and recorded savings of about N8.5 billion.

The programme built on work done in 2024, when MTN replaced 86 outdated cooling systems with more energy-efficient units across data centres, switch centres, and telecom sites.

In 2025, the company expanded its strategy further by replacing diesel-powered systems with gas-powered electricity and inverter solutions, while also increasing its solar-powered rural telephony sites from 194 to 229 to improve connectivity in underserved communities.

The progress, however, has occurred within stark realities.

Diesel made up of 58.11% of the telco’s total energy consumption in 2025, far exceeding gas-powered independent power producers at 23.63% and electricity from the national grid at 18.04%, with renewable energy contributing just 0.05%.

This is not merely an environmental challenge but a financial one. MTN estimates that powering its nationwide network with diesel costs more than N60 billion every year.

Nigeria’s power sector is marked by persistent grid instability, with 12 national grid collapses reported in 2024 alone, conditions that continue to force telecom operators to lean heavily on generators to sustain network operations.

Notably, MTN Nigeria was one of only four Nigerian companies (alongside Seplat Energy, Access Bank, and Fidelity Bank) that published inaugural financial reports using IFRS S1 and S2 sustainability reporting standards as early adopters, well ahead of the mandatory compliance deadline.

More than one-third of MTN Nigeria’s major suppliers have also aligned with the company’s long-term environmental goals, focused on reducing emissions across its supply chain and operations.

Dr. Karl Toriola, chief executive officer, MTN Nigeria, described the 2025 report as “an important milestone in our commitment to IFRS S1 and S2-aligned disclosure and accountability,” adding that sustainability remains central to the company’s long-term value-creation strategy.

In presenting the 2024 report, Toriola had similarly anchored the company’s ambition to the dual imperatives of building business resilience and unlocking long-term value a consistency of message that suggests the techo’s climate commitments are not a seasonal gesture but a structural shift, even if the road to net zero remains long and diesel-drenched.

In September 2025, Nigeria strengthened its climate goals, committing to reduce emissions by 32% by 2030 while promoting greener jobs, innovation, and a fair transition to a low-carbon economy.

Before then, MTN Nigeria was working to expand its own climate efforts.

In its 2024 Sustainability Report, the company disclosed an 11% reduction in Scope 1 and 2 greenhouse gas emissions compared to 2021 levels.