At 11 years old, Lincoln is both the middle child and the only son of the Loud family. He attends the 5th grade at Royal Woods Elementary School.
As revealed in "Not a Loud", Lincoln was born in the limousine of the President of the United States. After Vanzilla broke down, the President's limo picked up the Loud parents on the way to delivery. When in the car, Lincoln needed to get out then, so the President tried to deliver Lincoln, but fainted. Lincoln was delivered by the First Lady of the United States.
Lincoln often speaks to the viewers about how he gets around his often-chaotic household, the insane antics of his sisters, and other things he does. He possesses a habit of reading comics, manga, and novels in his underwear. Along with Lucy, he's the quietest of the 11 Loud siblings.
Lincoln is a good-hearted and well-meaning person, who is always looking for fun, and thinking about the well being of others. As the family nerd, along with Lisa, Lincoln is an avid fancier of comic books, manga, video games, fantasy and science fiction stories, which are typical interests for a boy his age. His favorite comics are Ace Savvy, David's Castle, and Comix Jokes. His favorite music band is SMOOCH, as seen in "For Bros About to Rock" and "Yes Man".
He is known to be "the man with a plan", as he is usually elaborating plans with a specific objective, most of them for his own benefits. His plans rarely succeed because of his own selfish and reckless decisions or by his sisters' interference. When he goes too far, he will always find the solution even if that means making himself look like a fool, as seen in "Making the Case" and in "Sleuth or Consequences".
Lincoln's best friends are Clyde, Zach, Rusty, Liam, and Ronnie Anne. Sometimes, he tries to hang out with other kids, but the rest of his social life has not really been explored and it's been revealed that when he tries to make new friends they're always being mean to him, as seen in "Save the Date" and "Hand-Me-Downer".
He's a very individual person with limited experience of teamwork in contrast to his sisters who cooperate as roommates, which was shown in "It's a Loud, Loud, Loud, Loud, House".
Most of the time Lincoln is quiet and relaxed, but sometimes he gets upset when he is annoyed, or when something goes wrong. Also, he has proved to be very patient, especially with his sisters. His greatest fear is the family falling apart, as shown in "Butterfly Effect", along with being hated by his sisters, as shown in "Making the Case".
Something that Lincoln has shown is that he is a multi-faceted person. Thanks to a life of living with ten sisters, each with a different personality, he is adapted to them, so he can communicate with any of them, and help them with their activities without a problem. Living in a female dominated family caused him to develop typically feminine traits, like kindness, sensitivity, cooking, beauty pageant knowledge, and sewing skills.
He acts as the "Jack of All Trades" to all of his sisters. He is not as good as his sisters in what they do, but he is competent enough to impress and help them in what they are doing: such as helping Lucy write her poems, being one step ahead of Luan in her pranks, preventing Lisa's experiment from exploding by adding a chemical, assisting Leni with her fashion designing, and catching Lynn's football in "Project Loud House". He is also the only one Luna complemented when the Loud House siblings were playing instruments in "House Music".
The episode "Study Muffin" showed he's a responsible student, has good grades, and doesn't really need a tutor, unlike Lynn, Lucy, Lana, and Lola. This makes him the second smartest of the Loud siblings, after Lisa.
Lincoln is also a very accepting, compassionate and respectful person, as he shows no ill will towards Clyde's adoptive gay parents or CJ's Down Syndrome.
Lincoln is incredibly calm, as in the episode "Not a Loud", he wasn't panicking about the possibility of being adopted. He was also calm when he was telling his parents about the clues that made him believe he's adopted.
Like most of the characters, Lincoln’s very skinny and has a large, round head with short white hair, and a large tuft of his hair sticks up. He has an overbite, with a prominent chipped front tooth, noticeable bags around his eyes, and freckles on his cheeks. Like some of his sisters, he also has grayish purple eyelids. In "Making the Case", it is revealed that he has one strand of chest hair. In "The Whole Picture", Lincoln had grown his first mustache hair.
His white hair is a unique feature that Lincoln has. He's the only one in the family with this hair color, as his sisters are either a brunette, or a blonde (with the exception of Lucy, whose hair is black, and as of "Spell It Out", it is proven to be her natural color).
Lincoln usually dresses in an orange polo shirt, blue jeans, gray socks with blue and red stripes, and white sports shoes with red stripes. His sleepwear is an orange nightshirt with matching pants, but sometimes he wears an orange t-shirt and his underwear. His swimsuit is a pair of orange trunks. He always reads his comic books in white briefs and socks, but on some occasions, he reads his comic books in his full outfit.
His winter outfit consists of a red coat, with red gloves, a brown hat, and brown boots. He also wears brown ice skates.
Lincoln's second-oldest sister, Leni, is quite fond of his white hair. She says it reminds her of their Pop-Pop and gets defensive if anybody mocks Lincoln for it, as shown in "Chore and Peace" and "Ties That Bind".