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What is the deadline for filing business taxes?

The deadline depends on how your business is structured. Different entity types have different due dates, and missing them means penalties even if you don’t owe money.

Sole proprietors and single-member LLCs file on Schedule C with their personal tax return. That deadline is April 15 for most people. C-corporations with a calendar year end also file by April 15.

Partnerships, multi-member LLCs taxed as partnerships, and S-corporations have an earlier deadline. March 15. These entities issue K-1s to owners, who then include that information on their personal returns. The earlier deadline gives owners time to receive their K-1s before the April 15 personal filing deadline.

Extensions are available for all entity types. File Form 7004 for business returns to get an automatic six-month extension. But an extension to file is not an extension to pay. If you owe taxes, you’re expected to estimate and pay by the original deadline. The extension just gives you more time to complete the paperwork.

Missing the deadline triggers penalties. The failure-to-file penalty is 5% of unpaid taxes per month, up to 25%. The failure-to-pay penalty is 0.5% per month. Interest accrues on top of both. These add up quickly, especially if you owe a significant amount.

Estimated taxes add another layer. If your business is a pass-through entity like an S-corp, partnership, or sole proprietorship, the income flows to your personal return. You may need to make quarterly estimated tax payments throughout the year to avoid underpayment penalties.

The best approach isn’t scrambling every March. Small business bookkeeping throughout the year means your records are ready when deadlines arrive. You’re not digging through receipts in February trying to figure out what you made last year. You know your numbers, your tax preparer has what they need, and filing becomes straightforward instead of stressful.

If you’re unsure about your specific deadline or need help understanding what applies to your situation, working with a professional for business tax preparation can prevent costly surprises and keep you compliant.

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