In the United States, it depends on the species of owl. Some owls are protected under the Migratory Bird Treaty Act and cannot be kept as pets without a permit. Other owls, such as the barred owl, great horned owl, and snowy owl, can be kept as pets in most states without a permit. However, some localities may have additional regulations, so it is important to check the local laws before getting an owl.
In Canada, it is illegal to own an owl without a permit. The permit can be obtained from the Canadian Wildlife Service.
In Europe, the laws vary by country. In some countries, it is legal to own an owl without a permit, while in others it is not. It is important to check the laws in your country before getting an owl.