Worldwide (with subscription):
* Funimation: Has both the original Black Lagoon and its sequel, Black Lagoon: Roberta's Blood Trail.
* Crunchyroll: Offers Black Lagoon and Black Lagoon: Roberta's Blood Trail in various regions, including North America, South America, Europe, Australia, and more.
Region-specific:
* Netflix (Japan): Offers both series.
* Amazon Prime Video (Japan): Has both series.
* Hulu (Japan): Offers Black Lagoon.
* Netflix (Latin America): Offers Black Lagoon.
Other options:
* YouTube (with purchase): You can purchase individual episodes or the complete series.
* Google Play Store (with purchase): You can purchase individual episodes or the complete series.
Before watching, it's important to check the availability of the series in your region.
You can also check websites like [JustWatch](https://www.justwatch.com/) to see where Black Lagoon is available in your region.