U-18chan is an English furry bulletin board which began as a merger of Aurorachan's /fur/ board into an IB4F board in late 2009, before it was forced to become an independent website in November 2010. For the most part, it is a “furry porn” website according to their own staff.

In 2009,¹⁾ the community at Aurorachan's “Furry” (/fur/) board, known as the “Aurorafurries”, would routinely raid 4chan's “Random” (/b/) board as a way to advertise themselves to furries on /b/ while also trolling their anti-furry sentiments. The community would later coordinate in a Xat chatroom, established by /fur/ moderator “Serpentor”, and it rapidly became apparent that the one board format was extremely limiting.²⁾

On June 26, 2009, after failing to set up a Kusaba X website, “Filthy” and “AlienSloth Man” (later “Jay”) would establish FilthySlothChan at IB4F³⁾ which then became U-18chan on October 22, 2009⁴⁾ since they joked that they evaded raids like a U-18 submarine. The AuroraFurries would migrate to U-18chan by November 2009,⁵⁾ then “Serpentor” vanished⁶⁾ and Aurorachan deleted the board in March 2010.

After registering numerous U-18chan domains,⁷⁾ “Infinitus” was forced to shut IB4F down in November 2010,⁸⁾ forcing U-18chan to use their new “u18chan.com” domain and restart with a fresh Kusaba X installation on December 2, 2010.⁹⁾ During this time, U-18chan temporarily borrowed Krautchan's mascot, Heinrich, since he conveniently fit in with the website's unusual aesthetics until he was replaced on July 13, 2011.¹⁰⁾

Due to Kusaba X's performance issues, the U-18chan staff inherited IB4F's Kusaba X fork from “Infinitus” and installed it on July 28, 2011.¹¹⁾¹²⁾ Five years later, a power surge would kill their hard drive in July 2016,¹³⁾¹⁴⁾ forcing U-18chan to salvage what was left and rebuild the server, while moving to a new datacenter, then they returned on July 24, 2016¹⁵⁾¹⁶⁾ though the news post¹⁷⁾ shows an incorrect start date.¹⁸⁾

In September 2023, there was a server failure and, since the U-18chan staff had no idea who had control of the website's Twitter or FurAffinity accounts, they ended up placing an invite link to the official U-18chan Discord server on the front page.¹⁹⁾ As of 2024, the U-18chan staff does have plans to replace the Pawstika with a new U-18chan logo, but it hasn't gone into effect as they're still dealing with technical issues.

^{Note: This list was retrieved on 2021-11-14. It may have changed since then.}

• The U-18chan mascot, a female sergal in an SS uniform, was designed by “Yuuri” or “YuuriArtz”.²⁰⁾ She was given her name, “Valkyria”, in a community vote that concluded on August 28, 2011.²¹⁾
• U-18chan once had a “Scalies” (/scale/) board, but it was closed in 2017 and was eventually deleted.
• On April 18, 2017, the U-18chan staff published a statement that U-18chan doesn't condone Nazi ideology,²²⁾ despite the website's continued use of “Nazifur” aesthetics and “Pawstika” imagery.

• U-18chan - The front page of U-18chan.
  • @u18chan on Twitter - The official U-18chan account, though it hasn't updated since 2019.
• U-18chan on WikiFur