In my safe harbor 401(k), I have participants that are terminated. Now, I understand that based on the type of safe harbor I have, I must give all terminated eligible participants a 3% of comp contribution. My question is if a participant is eligible to participant on 7-1-03 and terminates 9-20-03, do I have to give them a 3% safe harbor contribution for their comp from 7-1-03 to 9-20-03 or do i only have to give a safe harbor contribution to participants who had entered the plan before the 2003 plan year?

Well, the least would be the 3% of compensation earned while a participant. However, it depends on your document. It may define the least as being 3% of compensation for the whole year. Also, if the plan is being used in a cross-tested plan, the minimum might be 5% (or more). So, you need to check the plan document to see what it says and then make sure that nothing else gets broken in the process.