Updated 9/28/2026
Most business taxes can be significantly more complicated than personal taxes. However, it’s not unusual to file your own taxes if you're a Sole Proprietor, as the business taxes are hosted on the same form as your personal taxes.
If you're a Sole Proprietor, let's talk about what you need to file (and what to watch out for)!
CSI Accounting & Payroll has been filing business and personal taxes for 60 years, so we know the things that Sole Props commonly want to know when filing their taxes:
- What documents are needed to file Sole Proprietor taxes.
- What forms are used to file Sole Proprietor taxes.
- The top missed items for Sole Proprietor taxes.
Documents to File Sole Proprietor Taxes
Even if you’re working with an accountant, you need to know which documents to bring to business tax filing appointments. Nobody wants to hear “it depends,” but... it depends!
Most Sole Proprietors work as contractors and are going to need Forms 1099 from the companies you’ve worked for this year. Your total revenue should match your 1099.
You will also need your Income Statement and Balance Sheet to show what categories of expenses you had. When you work with a monthly accountant, you will already have these documents. If not, you may need:
- Credit card statements.
- Bank statements.
- Loan documents.
- Payroll reports (if your accountant does not handle your payroll).
- Invoices for large vehicle or equipment purchases.
- Sales and sales tax reports (typically for retail businesses).
- Inventory reports (for retail businesses).
- Accounts receivable and accounts payable (if applicable).
Having trouble distinguishing your personal finances from your business finances? A dedicated business bank account and a dedicated business credit card help you see which transactions are business-related.
Forms to File Sole Proprietor Taxes
Typically, Sole Proprietors just trust their software or their accountant to provide all of the forms they need. However, there are thousands of tax forms, and the ones you need depend on your unique situation, income, and expenses.
Remember, you'll need to complete Schedule C as part of your personal tax return.
Tax software doesn’t elaborate on the forms it uses. It can guide you for the most part, although many people find it confusing, not very upfront with pricing, and not as beneficial as working with an accountant.
While accountants can experience human error just like everyone else, a great accountant will have enough education and experience to use the correct tax forms. Plus, if you’re a Sole Proprietor who’s having an accountant handle your personal taxes, you’re probably going to have them handle your business taxes as well.
Top 4 Missed Sole Proprietor Tax Items
Since CSI Accounting & Payroll has been involved with Sole Proprietor tax returns for 60 years, we’ve picked up on some trends.
Here are the top four missed Sole Proprietor tax items:
- Depreciation records the cost of an asset and the period of time it needs to be expensed over. This is done on a separate form.
- Automobile expenses, including business miles or actual expenses on the depreciation schedule. If you report an expense amount but don’t report details of the expense, it automatically triggers a letter from the IRS.
- Independent contractor dollar amounts to match Forms 1099. If they don’t match, it’s a red flag to the IRS to look deeper at your finances.
- Certain elections that the IRS allows that, if not taken on a tax return, can cause you to miss some deductions available to you.
One Accountant for Business & Personal Taxes
If you own a corporation or partnership, you know how complicated business taxes are and probably already work with an accountant. However, if you’re a Sole Proprietor, you now know more about the documents and forms it may take to do your taxes, as well as the commonly missed items on your tax return.
While it’s certainly possible to do your own personal and business taxes, there are still many who work with accountants.Monthly accountants bear even more benefits, including categorizing all of your transactions and generating the financial statements needed to prepare the tax return. It takes a ton of time to do these things yourself!
At CSI Accounting & Payroll, we also analyze your current entity type each time you get a tax return to ensure it’s the best entity for you as you grow. While most of our clients are S-Corporations, we also accept other businesses that are the right fit to work with us.
Want to have a discussion about if we can be a good match? Click the button below for your free consultation!
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