Immortality is the power to live forever.
Immortality is the power that all witches and warlocks possess in varying forms. There are several forms of immortality, like Reincarnation and Wendy Beauchamp's nine lives (due to her being able to shapeshift into a cat). However, immortality is not invincibility. It is difficult, but not impossible to kill an immortal witch. Joanna Beauchamp can only be killed by Argentium poison, other attempts will not kill her. Other witches also possess immortality. However, when they are killed, they die. Penelope had the power of immortality but when she was thrown into the furnace by Joanna and Wendy Beauchamp, she was incinerated.
- Before leaving Asgard, Joanna Beauchamp was cursed with endless motherhood, thus giving her immortality.
- One of the only few ways to kill Joanna is Argentium.
- Joanna was almost killed permanently by Penelope Gardiner using Argentium until she was healed by Frederick.
- Wendy was immortal in Asgard until she was cursed with only nine lives.
- Wendy remains the same age she was when she left Asgard. If she is killed she will lose one out of nine lives but will remain the same age.
- Ingrid was immortal in Asgard until she was cursed to be reborn after she dies and never live past 30.
- Freya was immortal in Asgard until she was cursed to be reborn after she dies and never live past 30.
- Penelope was able to live for over a century.
- Archibald has not aged ever since he and the others of his kind were banished from Asgard.
- Harrison, an ally and lawyer of Joanna Beauchamp, was in Asgard and has not aged even after hundreds of years.
- Vidar who was alive with Joanna during the Salem Witch Trials has not aged and came back to kill Joanna for revenge after she cut off his ear.
- Frederick has not aged even after hundreds of years.
- Tarkoff has not aged even after hundreds of years.
- Isis has not aged since being banished from Asgard over 400 years ago.
- Ivar has not aged since being banished from Asgard over 400 years ago.