I am wanting to transfer my H1-B visa to a new employer, given that I am offered the job. I have had the initial telephone interview and am going for my face-to-face interview first with the HR dept. and then the specific Dept. Manager. Is now the best time to tell HR about my visa status or is it better to wait till I am offered the job?

Should I tell HR during my interview about my visa status if I am not asked that ? I don't want my status to give me a disadvantage but at the same time I do not want to give HR an impression that I did not disclose an important fact to them. This is a tricky situation so it would be great if I could get some input from people who went through a similar situation and their experiences. Thank you.

It depends upon nature of talk you will have. If they ask for your status, then it is better to tell about it otherwise they might consider you as a liar. If that issue is not arose in interview then reman silent until you are offered job. If this job is very important to you, you can also tell them that you are ready for lawyer expenses (in case if they are not ready to pay related expenses).
H1B transfer should not be a problem but you should at least file the application to USCIS before starting the work.

Thank you. I appreciate your response and will take your suggestions into consideration. Does anyone else have any experiences or suggestions?