Family name Jonnsen (Jonnsen 
) , all around the world, is a very rare last name. The cognomen Jonnsen is characteristic of Tanzania, where it is a very rare surname, and the United States, where it is an extremely rare surname. Much less frequently, Jonnsen is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Jonnsen | United States, Philippines, Tanzania |