Invitation is a weakness of vampires and hybrids, including Original vampires/hybrids. In order to enter any house owned by humans, witches, werewolves, or doppelgängers, vampires or hybrids must be invited by the owners of the home. Once invited, the vampire cannot be uninvited unless the ownership of the house changes.
This protection appears to manifest itself as an invisible barrier that automatically erects itself on the door lintels and any available entrance in a human home if a vampire tries to enter that dwelling without an invitation from the owner. These barriers are extremely strong, as they are among the few known ways to keep vampires at bay, if killing them is not an option. The barrier only holds for as long as the vampire remains uninvited and the dwelling remains standing. Because of this, vampires have been frequently known to resort to other methods to enter the house, such as setting the house on fire to either destroy the home or to drive the humans inside out of the house and the protection it provides, or by otherwise destroying the house.
Vampires have been known to use this weakness to their advantage, by establishing a home with a human owner, as to keep out other unfriendly vampires.
It is somewhat unknown what happens to a conscious vampire who is in a human's home into which it was invited at the same time that the ownership changes. In The Dinner Party, Elijah is daggered and brought into the Salvatore Boarding House while the house is still in the name of (deceased) Zach Salvatore, and any vampire can enter it without an invitation. While Elijah is daggered in the basement cellar of the house, the Salvatore brothers have a lawyer transfer ownership to Elena in order to use it as a "safe house" from any vampires who try to hurt or abduct her for Klaus. When Elena undaggers Elijah some days later, Elijah awakens and is disoriented and unable to breathe, having difficulty controlling his body until he finally runs out of the house. It seems unlikely that a fully conscious vampire can be forced into a house where it has not been invited. however Silas is the only vampire shown to be able to enter person's house without being invited in.
Unlike Its counterpart in TV, vampires can enter homes when they are invited in by anyone in the house, regardless of whether they live in the house, are the owner, or are a guest. However, if a house contains old structures of the original house along with renovated portions of the house that were added much later, the vampire must be invited into those parts of the house by only the original owners; for example, Elena says that her bedroom and the living room are part of the original house, so Katherine von Swartzschild, Damon Francesco Salvatore and Stefan Antonio Salvatore cannot enter these rooms, as the original owners are no longer living and are unable to invite them in.
In the TV series, if a vampire is in a house without a human owner, or is invited in by the owner, and then the ownership of the house is changed while the vampire is still in the house, the vampire will become disoriented and will begin to feel as though they are suffocating. This is shown when Elijah is resurrected by Elena after the ownership of the house is transferred to her, he is unable to breathe until he leaves the house.
- The idea that vampires need to be invited to enter homes or residences has different meanings, but the principle is mostly the same (Protection against undead).
- In some stories, vampires can not enter homes because it is inhabited by living things, and it's like being underwater, murky and full of life.
- In The Vampire Diaries, vampires were not created by the planet compared to the other species. As a defense, nature attacks the vampires with sunlight, wood, vervain, and other elements (for example, water weakens vampires in the books). With the purpose to defend against the undead, the living kept the vampires away by banning them entry into their homes. Literally, it's like saying: I invite my own death to my home.
- The origin of inviting a vampire into a home is in the novel Dracula by Bram Stoker. It is mentioned that Dracula was always invited to the homes, causing suspicion about this feature because in those days, people of a high social class invited other people of the same class as a form of education and respect. Because Dracula looked, talked and moved like a person of high social statue, it was easy for him to gain an invitation into others' homes.
- When Bonnie traps Niklaus in the Gilbert House, it is a reference to the books.
- In the books, Elena's room, and living room are part of the original construction of the house, and vampires cannot enter these places due to not having an invitation by the original owners.