Can I do BA (honors) in economics? I am a commerce student.

Yes, you can. You already studied economics in your stream. Also, it is a commercial subject. So, you can do it.

Yes, Economics is a good course to pursue your graduation in. It is even better, if you are a commerce student compared to Science student.

You are eligible for BA (Hons.) economics in a majority of universities with your commerce background. However, you are advised to review detailed eligibility criteria in your targeted university.