Short answer
It varies by state, from same-day or a few business days to a few weeks for standard processing, and many states offer expedited filing for an extra fee. After the state approves the formation, additional steps like getting an EIN, opening a bank account, and any required licenses add time before you can fully operate.
The formation itself is the state approving your articles of organization. Some states process online filings in a day or two, while others take a couple of weeks during busy periods, and most sell an expedited option. The filing time is only part of the picture.
To actually run the business you usually also obtain an EIN from the IRS, set up banking, and secure any licenses your activity requires, which can take longer than the formation. Planning those steps in parallel keeps the launch moving.
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