The business entity provided consulting work for a one company only. Hence, only a single 1099 has to be filed.
Do I need to amend my personal taxes or file business taxes separately under the EIN (sole member LLC and no employees)?
If you are a single member LLC then you would need to Amend Your Return to include the 1099 income on your personal return. This will be reported on Schedule C.
A sole proprietor LLC that has not specifically filled out additional forms to be treated as a corporation reports all business income and expenses on their own personal taxes using Schedule C. There is not an additional business return required.
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