Many characters names in the Ultimate Marvel universe are different from the mainstream universe.
- Ultimate Spider-Man:
- The Prowler's name is changed from Hobie Brown to Aaron Davis.
- The Tinkerer is known as Elijah Stern rather than Phineas Mason. Then again, a character named Phineas Mason later appeared in an Ultimate Fantastic Four annual, so if anything, the Ultimate Tinkerer is a Decomposite Character.
- Captain Stacy's first name changed from "George" to "John." Gwen's mother's name is now "Madeline" instead of "Helen".
- Similarly, Flash's first name was changed from "Eugene" to "Fred"
- Walter Hardy's first name was changed to "Jack."
- Spot's first name was changed from "Jonathan" to "Frank."
- The Enforcers also got hit with this. Fancy Dan's last name went from "Brito" to "Crenshaw", Ox's real name was changed from "Raymond Bloch" to "Bruno Sanchez," and Montana's real name went from "Jackson Brice" to Montana being his real first name and his last name being "Bale." Frederick Foswell's real name remains unchanged, but his codename went from "The Big Man" to "Mr. Big."
- Martha and Billy Connors are renamed Doris and Timmy Conners. The former is also a Continuity Snarl as the family's debut in Ultimate Marvel Team-Up sees a letter to Curt's wife named her "Marsha"—and later in the same issue the 616-name of "Martha".
- Curt Connors's last name itself is modified is to "Conners" and likewise, the spelling of "Jean DeWolff" is modified to "Jeanne DeWolfe".
- Emily Osborn's first name is changed to "Martha."
- Ultimate X Men
- The Brotherhood is a minor but significant one; they're the Brotherhood of Mutant Supremacy rather than simply the Brotherhood of Mutants, reflecting their Super Supremacist attitude. Although for the longest time they were just called the Brotherhood of Mutants. They certainly don't call themselves the Brotherhood of Evil Mutants, because from their perspective, they're not.
- The New Mutants are reimagined as the Academy of Tomorrow.
- The Blob's first name is "Franklin," not "Fred."
- As Proteus is a Composite Character of his classic counterpart and Legion, he retains the latter's first name of David. However, as Professor Xavier and Moira MacTaggert, unlike the classic Xavier and Gabrielle Haller, were married when they had him, he has Xavier's last name. Moira herself is this, as "Kinross" was her maiden name in the mainstream universe and the name "MacTaggert" being part of a very bad marriage and her husband refusing to divorce her because of his political career. Here, MacTaggert is her maiden name.
- In mainline comics, Rogue's real first name is Anna-Marie with her surname unknown. In the Ultimate universe, her full name is Marian Carlyle.
- In the classic Marvel Universe, Quicksilver and the Scarlet Witch had the last name "Maximoff". Here, as they were raised by Magneto, their last name is "Lensherr".
- As is Magneto himself. While his real name, Max Eisenhardt, wasn't revealed until around the time of Ultimatum, one of the many aliases he used was Erik Lehnsherr. Here, Erik Lensherr (only one "h") is his actual name.
- In the main universe Longshot is simply Longshot (although he appears in X-Men comics he's not a mutant but someone from another dimension, with other naming traditions). Here, as he had an Adaptation Species Change into just another mutant, his real name is Arthur Centino, and "Longshot" is his mutant name.
- Strike is a subtle one. She's Lady Deathstrike in the regular continuity, but here she is just Deathstrike. Similarly, she usually just goes by "Yuri" though her real name is still Yuriko.
- The Ultimates as a group are an example, renamed from "The Avengers."
- Tigra's name is changed from Greer Nelson to Marie Grant.
- Tony Stark's real name is "Antonio" rather than "Anthony."
- As natives of the Savage Land, the Ultimate versions of Ka-Zar and Shanna the She-Devil always seem to have those names, whereas the mainline Ka-Zar was a man from England named Kevin Plunder and the mainline Shanna (an American-Zairian) has the last name O'Hara.
- As Loki is the biological son of Odin and not an adopted one, his last name really is "Odinson," not "Laufeyson."
- Ultimate Fantastic Four:
- Doctor Doom's last name is "Van Damme," not "Von Doom."
- Reed Richards's father's first name is "Gary," not "Nathaniel." However, with absolutely no similarities between both characters (besides being Reed's father), it may be easier to consider him a brand new and unrelated character.
- Mole Man's name is changed from "Harvey Elder" to "Arthur Molekovic."
- Possibly to separate him from Gah Lak Tus's heralds, the Ultimate version of Norrin Radd is called "the Silver Searcher".
- Diablo's real name is changed from "Esteban Corazón de Ablo" to "Mendendez Flores".
- Ultimate Galactus Trilogy
- Galactus is renamed as Gah Lak Tus.
- Captain Marvel's real name is changed from "Mar-Vell" to "Geheneris Hala´son Mahr Vehl," usually shortened to "Mahr Vehl."
- His Kree superior, Yon-Rogg, was renamed as Yahn Rgg.
- Ultimate Daredevil & Elektra renamed Elektra's father from "Hugo" to "Stravos", then Ultimate Elektra inflicted a Continuity Snarl by renaming him yet again to "Dimitris".
