It mostly depends on your own implementation of the ''no God exists'' thesis, and the definition you give to the word religion itself.
Leaving aside that mine was a play of words, at a very basic level you still don't have any proof that God does not exist (and you will never have that). It is true that most atheists (as myself) use logic to defy religion, but at the very end, it's still a belief.
Then, when you take things to extremes, I do like to call ''religions'' a broader amount of things, from soccer teams to ideology.
But keeping things literally, the ''demonstrably not faith based'' form of atheism is agnosticism.