Where to watch
Not available in United States
Streaming in 1 other country
The Flat Sum isn't on any streaming service in United States right now, but it's available in Japan. Streaming rights are licensed per country.
More like this
9 Souls
2003 · 6.4
Battles Without Honor and Humanity: Deadly Fight in Hiroshima
1973 · 7.3
Return of the Street Fighter
1974 · 6.1
Boiling Point
1990 · 6.9
Baby Assassins 2
2023 · 6.7
Crows Zero II
2009 · 7.2
Bayside Shakedown 3: Set the Guys Loose
2010 · 5.0
Lupin the Third: The Mystery of Mamo
1978 · 7.0
Gozu
2003 · 6.8
Hero
2015 · 6.1
Lupin the Third: Dead or Alive
1996 · 6.6
Lupin the Third: Blood Seal of the Eternal Mermaid
2011 · 6.2
The Flat Sum — streaming FAQ
Which OTT platform streams The Flat Sum?
The Flat Sum isn't on any streaming service in United States yet, but it's available in Japan. Streaming rights differ by country — switch your country in the header to see where.
Is The Flat Sum on Netflix?
No, The Flat Sum is not on Netflix in United States as of October 2026.
Is The Flat Sum on Amazon Prime Video?
No, The Flat Sum isn't on Amazon Prime Video in United States right now.
Where can I watch The Flat Sum for free?
The Flat Sum isn't streaming in United States yet, so there's no way to watch it free at the moment.
