@swamilikes2code That old issue is ancient, and probably should be closed just because it’s hard to know what is relevant or not anymore. Nominally I would say that Bokeh strips all tz info and does not send any tz info to BokehJS. The latter statement about not sending tz info is certainly the case, so I’d still say tz-formatting of ticks is best handled by a FuncTickFormatter. But some experiments have me wondering about the first part about stripping tznfo wrt to pandas specifically. Can you construct a small, complete, toy example for me to investigate? It may be that a new issue is in order.