DD1 was off the bottle at 10 months.
DS wouldn't give the bottle up until he was 15 months old, we tried to wean him off and he simply wanted NOTHING to do with the sippy.The pedi said to throw the bottles away and only give the sippy until he took it. Took him almost a whole day, but he finally accepted it.
I started sippy cups at 3 months old, and she was using only sippy cups in the day time, and had 1 bottle before her nap and one at night time, but she is 13.5 months old now and has been off the bottle 100% at 8 months old :)
She now is just on whole milk.