If you run an LLC, you must file taxes yearly even if your business makes no money. This is because you may still be liable for taxation on business expenses such as office rent or utilities. If you don't do so, you may be subject to fines or penalties.
And if you decide to use 1-800Accountant, you won't have to worry about any of that because 1-800Accountant will review your tax return and ensure you never miss a filing deadline.
There are some exceptions to this rule, such as if your business is a sole proprietorship, but it's always best to check with an accountant or tax attorney to be sure.