.io domain's fate uncertain? 16% of Web3 companies use .io

By Karen, Foresight News

The United Kingdom has relinquished sovereignty over the British Indian Ocean Territory (BIOT), specifically the Chagos Archipelago, and transferred it to Mauritius—a historic moment marking the end of British colonialism in Africa. At the same time, this development has sparked widespread debate about the future of the highly popular .io top-level domain.

What happened?

Against a backdrop of intensifying geopolitical competition, on October 3, the UK and Mauritius issued a joint statement announcing they had reached a historic political agreement regarding sovereignty over the Chagos Archipelago. Under the terms of the treaty, the UK will recognize Mauritian sovereignty over the Chagos Islands, including Diego Garcia, home to a joint US-UK military base. Although the final treaty remains to be formalized, both parties have committed to completing the process as quickly as possible.

However, with the transfer of sovereignty over the Chagos Islands to Mauritius, the future of the .io top-level domain has become uncertain. This change could have profound implications for the many websites using .io domains. The .io country code top-level domain (ccTLD) was originally assigned to the British Indian Ocean Territory (BIOT) and is managed by a UK-based private company, Internet Computer Bureau (ICB), which is now owned by U.S.-based Identity Digital.

The ".io" TLD derives from the two-letter ISO code "IO," representing the British Indian Ocean Territory (BIOT)—a British Overseas Territory—and functions as its country-code top-level domain (ccTLD) within the internet's domain name system. The .io domain extension has existed since 1997; the first registered .io domain was levi.io, claimed in 1998 by clothing company Levi's. According to a 2014 report by The Independent, "the UK government receives a share of profits from the sale of internet domains linked to the Chagos Archipelago in the Indian Ocean. Under an agreement with ICB, the government receives an undisclosed portion of the £60 fee charged for each activated .io domain." Paul Kane, founder of ICB and an internet infrastructure expert, confirmed that the UK government receives part of the revenue generated from .io domain registrations.

Historically, ccTLDs have been removed five times

The fate of ".io" lies largely in the hands of the Internet Corporation for Assigned Names and Numbers (ICANN). However, it’s important to note that ".io" is a country-code top-level domain (ccTLD), meaning political considerations outweigh technical or commercial ones.

ICANN, a non-profit corporation based in California, was established on September 30, 1998, to assume responsibility for managing internet-related tasks such as domain names and IP address allocation. According to Domain Incite, since ICANN’s founding in 1998, only five ccTLDs have ever been removed from the DNS root zone. In all but one case, the trigger for removal was a change in the ISO 3166-1 alpha-2 list maintained by the International Organization for Standardization.

1. ".yu" was the ccTLD for Yugoslavia. After the breakup of the Socialist Federal Republic of Yugoslavia in 1992, the rump state of Serbia and Montenegro retained the code until their separation in 2006. New registrations under .yu were suspended in March 2008, and ICANN finally removed .yu from the DNS root in 2010.

2. ".tp" was the ccTLD for Portuguese Timor, officially launched in 1997 while still under Indonesian occupation. After gaining independence in 2002 and becoming Timor-Leste, ISO assigned it the new code "TL" and removed "TP" from its list. However, the .tp domain was not fully phased out of the DNS root until February 2015.

3. ".zr" was the ccTLD for Zaire. After the country reverted to its former name, the Democratic Republic of the Congo, it adopted the .cd domain. The .zr domain was officially discontinued in 2001, making it the first ccTLD ever removed by IANA.

4. ".an" was assigned to the Netherlands Antilles, a group of Dutch Caribbean islands. After the dissolution of the Netherlands Antilles in 2010, Curaçao adopted .cw, Sint Maarten took .sx, and Bonaire, Sint Eustatius, and Saba received .bq. ISO removed "AN" from its list, and the .an domain was fully decommissioned by 2015.

5. ".um" is the ccTLD for the United States Minor Outlying Islands, but it was never actively used. In 2007, ICANN removed .um from the root zone list.

Notably, ".su"—assigned to the former Soviet Union and activated on September 19, 1990—remains an exception. Despite the USSR's dissolution decades ago, the .su domain is still operational today.

What’s next for .io?

According to ICANN’s ccTLD deactivation policy, eligibility for a ccTLD is determined by inclusion in the ISO 3166-1 standard. When a country or territory is removed from this list, its eligibility expires, and the domain must be phased out after an orderly transition period. By default, a ccTLD is scheduled for deletion five years after deactivation. Managers may apply for a single five-year extension with sufficient justification, making the maximum possible timeline for formal removal ten years. Alternatively, the ccTLD manager may choose to discontinue the domain earlier.

If a change in ccTLD eligibility is confirmed, the Internet Assigned Numbers Authority (IANA) will notify the ccTLD manager of its intent to issue a removal notice. The manager then has the opportunity to designate an alternative contact person to handle deactivation-related communications.

As Domain Incite noted, the central concern for .io registrants is whether the redefined British Indian Ocean Territory (BIOT)—if it continues to exist at all—will retain its "IO" designation on the ISO list and maintain its unique territorial status qualifying it for a ccTLD. If BIOT becomes merely part of Mauritius and is no longer recognized by the UN as a separate territory, the continued existence of the .io domain would face serious challenges and could ultimately be removed. Conversely, if BIOT retains its distinct territorial standing and ccTLD eligibility, the situation becomes more complex. There is also a small possibility that .io could follow the path of .su and remain active indefinitely—but this scenario is considered unlikely.

Which crypto companies use .io?

In computer science, "IO" is commonly used as shorthand for "I/O" (Input/Output), making .io domains naturally appealing for technology-related services. Combined with their brevity and modern feel, .io domains are especially popular among tech startups and software companies—and widely adopted in the crypto space. Additionally, .io is a preferred choice for browser-based multiplayer video games, where "io" has become synonymous with lightweight online gaming.

According to NetEase's "Tech World," platforms like Glitch and GitHub Pages use .io domains for user-hosted websites and applications, and the game marketplace Itch.io operates on the same extension. The .io domain industry is estimated to have generated around $40 million, suggesting over one million .io domains have been registered. Notably, the domain "Metaverse.io" sold for 1.14 million yuan ($160,000) in 2021—the highest publicly recorded price for a .io domain.

Among the approximately 20,000 Web3 projects and companies listed in Foresight Wiki, nearly 16% use .io domains, including Matter Labs, ZKsync, Arbitrum, Optimism, Scroll, Sei, Damus, CoinFund, Scallop, Mask Network, TrueFi, Raydium, DODO, and others. Notably, Gate.io uses its domain name as its brand identity.

Foresight News will continue to monitor the evolving status of the .io domain.