Superman: The Animated Series takes place simultaneously to The New Batman Adventures
Starting with the critically aclaimed Batman: The Animated Series, the DC Animated Universe (DCAU) is what made many of us fall in love with DC’s characters.
e have several DC animated universes. This timeline doesn’t cover all of them. But there is one that stands out above the rest. We present the DC Animated Universe, consisting of the Batman/Superman animated series, Justice League, Justice League Unlimited, Batman Beyond, etc. There were tie-in comics to these series that, as of right now, we do not include in the timeline. These tie-in comics are complex, and don’t always line up perfectly with the continuity of the shows they are based on. However, we will hopefully include them in future updates.
The DC Animated Universe (DCAU) is a fan term for a series of popular animated television series and related spin-offs produced by Warner Bros. Animation which share the same continuity. Most of these series are adapted from DC Comics properties. This continuity is also sometimes referred to as the Timmverse (after producer Bruce Timm, the continuity's most consistent creative influence) and in the past, the Diniverse (after writer Paul Dini, who had mostly departed from Warner Bros. Animation when Justice League was in production).
The official DC Animated Universe in a somewhat chronoligal order. Infos taken from all over the web. I tried to order some episodes differently, as you can see with Batman TAS' Two-Face 2 Parter - which is now separated by a couple of episodes, as the second part states that there were 6 months between the events of the two.