Portaberto is the incantation of a charm used to splinter a lock from a door, allowing the caster to bypass a locked door. It was the most popular unlocking spell prior to the discovery of the Unlocking Charm. Unfortunately, it has a side effect of occasionally leave a smoking hole where the key should have gone in the door.
Before the invention of Portaberto, the most popular unlocking spell was Open Sesame, which had the unfortunate effect of flagrantly tearing a door from its hinges and tearing it into firewood. With the invention of Portaberto, however, magically opening locked doors was made much more discreet and far less messy, by simply splintering the lock from the door, though it was still known to occasionally leave a smoking hole where the key should have gone. Later however, in the early 1600s, the Unlocking Charm was discovered, and became the most popular unlocking spell, superseding Portaberto and largely rendering it obsolete.
- Cerberus Langarm, an officer of the Department of Magical Law Enforcement, performed this charm during an investigation to gain entry to a secret Owlery belonging to Bilius Finbok. It was unknown if the spell was truly successful, as it was implied that the door had already been unlocked, either by Mathilda Grimblehawk or her partner during one of their past visits to the Owlery.
The incantation Portaberto is most likely a portmanteau of porta, "door" in several Romance languages including Latin, Catalan, Galician and Portuguese, and aberto, Galician and Portuguese for the adjective "open". Taken together, the incantation refers to the spell's capacity to open doors.
Interestingly, this spell shares a similar etymology with Aberto, ostensibly another door-opening spell. This suggests that these two spells may be related in some way.