I have an llc which i am the single owner, and, i have no employees.
when doing my schedule c, i was always entering my name, my company name, my ssn, and my LLC EIN on schedule c. even an accountant had done it that way for me several years ago when i started

yesterday another accountant told me, entering of EIN on schedule C is not necessary, and actually we should not, as it might develop the expectation of filing payroll taxes. what do you think about this? can you share experiences or thoughts?

he even told me that getting an ein was not even necessary for me in the first place until i will have employees.

I am in the same situation and have done the same. Would also be interested to know if I should not be doing this?

I agree that you don't necessarily need an EIN for a sole proprietorship but in certain states in order to register your LLC you need an EIN. As for filing an EIN on your tax return, I'm not sure how it would raise a red flag for payroll taxes, if you have no employees you have no employees. I got an EIN in 2011 and didn't have employees until 2014. If anything, your EIN makes your business look more legit versus looking like a hobby.