Single-member LLCs need to file an extension and they are considered as a disregarded entity by the IRS unless the business entity is classified as C Corporation or S Corporation. For Federal tax purposes, the Single-member LLCs are taxed as a sole proprietorship (Form 1040) and must request an extension using Form 4868.
If the business has opted to be taxed as C Corporation (Form 1120), an extension must be requested using Form 7004.
If the business has opted to be taxed as S Corporation (Form 1120S), an extension must be requested using Form 7004.
