[IPython 0.7.3 and 0.7.4] Hi, "\#" (maybe other special escapes, too) ignores the colour escape codes in prompts. See for instance . The "\#" is printed in green (although it should be white. Same goes for the out prompt where it's printed in red. Thorsten  prompt_in1 '\C_White[\#\C_White]\C_LightCyan>>> '