For Florida, whether you need to file a return depends on whether your LLC is a multi-member LLC or a single member LLC, plus as to whether you had any employees during 2018 (besides yourself or family members).
In general for Florida, all
corporations must file a corporate/franchise income tax return for their
business, even if the business is organized as a partnership or LLC.
For single member LLC’s and sole proprietors, though, a corporate income
tax return does not need to be filed
as the single member LLC /owner is not an
employee and his or her wages would not be taxable wages in Florida. But if the single member LLC or sole proprietor has employees, a
corporate income tax return needs to be filed as taxes are due on the wages
paid (unless the wages were paid to exempt employees such as a spouse, parent,
or child).
See more information
here: Florida Dept
of Revenue - LLC
