- In Kyon: Big Damn Hero, members of the SOS Brigade change the way they address each other as a symbol of their True Companions relationship is strengthening: Tsuruya is called Tsu-chan by Haruhi and Mikuru(big), and Yuki and Mikuru being called by their first names not only by Haruhi.
- Used in the The X-Files / Earth: Final Conflict crossover "Apologia." The young Agent Sandoval asks if he can address Scully as "Dana," because he refuses to give the impression that he's trying to take Mulder's place.
- A classic example of this trope appears in With Strings Attached when, as a sign of his complete Heel–Face Turn, the Hunter asks Paul to start calling him by his first name, Jim. He had already agreed to use the first names of the four that morning, rather than the insulting nicknames he'd come up with for them at the beginning. (Originally, when George said that they have names and would he care to hear them, he said “Not especially.”)
- In the Katawa Shoujo fic From Shizune's Perspective, Shizune temporarily switches to calling Emi by her first name rather than "Miss Ibarazaki" to make a point, then despite switching back to calling her by her last name, gradually switches over to her first name. She also points out that Hisao might be "interested" in Emi if he calls her by her first name, causing Misha to react in displeasure because she is in love with Hisao. Shizune also calls Misha by her first name, Shiina, in this fic, instead of her nickname.
- In Ace Combat: The Equestrian War, Lightning Bolt, Twilight Sparkle and Tornado Swirl are usually called Lightning, Twilight and Tornado. Cloud Kicker also applies to this, though rarely.
- Jessica Poole gets onto this with Apollo Justice: Ace Attorney during the second day of investigation in Turnabout Substitution, but retracts it the next day, much to Apollo's surprise.
- In A Complete Turnabout, one of the first clues that Phoenix gets regarding his new place in an alternate universe is that Edgeworth calls him "Phoenix" instead of "Wright," like canon!Edgeworth always does.
- A major part of Vinyl Scratch's Character Development in Vinyl and Octavia Machete Their Way Through The Jungle is the fact that she stops calling Octavia names like Tavi and Octy and instead calls her by her full name.
- Calvin and Hobbes III: Double Trouble has two characters named Rupert Chill - one human, one alien. The alien Rupert goes by his first name to avert confusion.
- Nav from Diaries of a Madman tends to be on first name terms with almost everyone he meets, royalty and commoners alike. Strangely enough, it's usually those accompanying him that protest over the lack of formality, rather than the recipients.
- Yuzu and Byakuya ran the whole gamut of names and titles in the Bleach fanfics Phases of the Moon and Chasing the Moon. While Yuzu was in the Academy and Byakuya was helping her train, Yuzu called him "Kuchiki-dono" (Lord Kuchiki) and Byakuya called her "Kurosaki Yuzu" (if he called her anything at all). While Yuzu was still an Academy student but chose to actively involve herself in a battle for the first time, she called him "Kuchiki-taicho" (Captain Kuchiki), signifying that she now sees herself as a shinigami and a (future) member of the Gotei 13. Ten years later, by the time of the sequel, Byakuya now calls her "Kurosaki", seeing as she's now his vice-captain, and Yuzu starts referring to him almost exclusively as "Taicho" (just plain Captain). As the Will They or Won't They? intensifies, they start thinking each other's first names without actually saying them out loud. They finally make it to First-Name Basis at the end of ''Chasing The Moon's'' penultimate arc. Too bad it happens in the last moment before Yuzu runs off on a Suicide Mission that appears to be Unwinnable by Design.
- Discussed in "Aen'rhien Vailiuri". Tovan tr'Khev tells Jaleh Khoroushi to call him by his first name, because Morgan t'Thavrau, his neighbor and friend for ten years on Virinat and now his captain, doesn't do that anymore and he misses it.
- In Out Of The Dead Land, Bucky initially switches back and forth between referring to himself and others in his head by their codenames or by their first names depending on whether he's trying to be the Winter Soldier or Bucky Barnes at that particular moment. As the fic progresses and he begins regaining his sense of identity, he eventually transitions to using first names only. Significantly, he does this first with Steve.
- In Shatterheart, Kurogane usually refers to Real!Syaoran as "kid," but when he and Real! transition from friends to Friends with Benefits Kurogane makes a point of calling Syaoran by his name when they're alone. Kurogane temporarily rescinds this when he ends their relationship. He goes back to using it when he and Syaoran rekindle their bond.
- In Vapors the main character muses on how few people ever even talk to a kage, let alone have a First-Name Basis with three of them. Later on, Anbu captain Fish has been grumpy that he got snubbed by being given a rookie agent for his team. Then they report to the Hokage, who immediately greets Butterfly by name and personally heals her rather minor injuries, while Fish silently freaks out.
- Fire Emblem Fates: Aftermath: Due to their close friendship, Silas is not obligated to call Corrin by his title of "King" and can just refer to him by his first name in casual conversation.
- In Return of the Hero, upon learning that Kelly isn't his biological mother, Nate starts addressing her by her name instead of "Mom". He reverts back to calling her "Mom" when she is taken hostage by Cassidy and Butch.
First Name Basis / Fan Fiction
Examples of First-Name Basis in Fan Fiction.