As a general rule the best times to tweet are 9am, 12pm and 3pm.
However you may also want to take into account:
1) Your location and the location of your target market for time zone differences
2) The times when you’ve had the most response to your tweets in the past
3) The need to engage with your followers. Try asking questions and seeing when you get the best response, you may find early evening is better, depending on your target market.
Or let us tweet for you and give your business that professional edge.