Okay, I'm going to work through the easy-case assumptions which I am most familiar with
Assumptions
- You are a sole proprietorship (although it is likely more tax advantageous to be an S-Corp or LLC if you can)
- You are therefore filing a schedule C for your 1040 (long form) individual income taxes
- You have no other income than that $100k in net profit from the business
- You are single, have no dependents, and are claiming the standard deduction (as someone who is neither blind nor elderly)
- You have no adjustments to income other than the SE adjustment (which is inherent to having a profitable business).
- You do not qualify for any federal tax credits.
- You are a US citizen and not anyone else's dependent.
Under Tax Year 2011 law You have to file a
1040 Long form
a Schedule C
a Schedule SE
As per the example, there is $100,000 in business profit, so I assume that someone else has already correctly worked through the Schedule C to determine that, and for my part I can just enter $100,000 on line 12 of the 1040. Although in reality I would never trust another preparer's work on a Schedule C -- it's a common source of both confusion and probable fraud. I have previously caught errors on this area of returns done by people with far more education, credentials and experience than myself on such things.
There's no other income, so that $100,000 carries down to line 22, total income.
There will be one adjustment to income. Since a sole proprietor is self-employed, they have to account for both sides of their payroll taxes, which is painful, but schedule SE allows them to exclude a portion of those taxes from their income for tax purposes. Assuming my quick math is correct, this works out to a $7064 adjustment entered on line 27 of the 1040.
This leaves an Adjusted Gross Income of $92,936 to be entered on lines 37 and 38.
You then subtract a $5800 standard deduction on line 40 and a $3700 personal exemption on line 42. This leaves you with a federal taxable income of $83,436, which as per the 2011 tax table is a federal tax liability of $16,981 entered on line 44. That's high enough that you will face penalties if you did not make quarterly estimated tax payments in advance.
However, you are also self-employed, so you are liable for both sides of payroll tax and must file schedlue SE. Assuming my quick-math is correct, that comes out to another $12,283 in taxes to be entered on line 56.
So total federal tax burden comes out to $29,264 under the most current tax law
Moving on to make some additional assumptions:
- The Bush cuts expire and tax rates reset to year 2000 levels.
- SE taxes, and the SE adjustment stay the same as they were for 2011
- The Standard Deduction and personal exemption amounts stay the same as they were for 2011
- No piece of tax law changes to make our example eligible for additional credits or adjustments.
These assumption let us simply look up the exact same amount of AGI in the [
http://www.unclefed.com/IRS-Forms/taxta ... 1040tt.pdf]tax tables for 2000[/url](which the IRS website seems to have an outdated PDF for)
yields an income tax burden of $20,543. We add the same $12,283 in SE taxes for a total federal tax burden of $32,826.
Thus, under these assumptions, the Bush tax cuts reduce taxes for our hypothetical small business owning taxpayer by $3,562.
Although those assumptions are likely generous. A taxpayer with that amount of income is highly likely to be eligible for various other ways to reduce their tax burden (for example having a mortgage, putting money in an IRA, paying student loans, having kids and/or being married) While such things would reduce the total federal tax burden under both current and pre-Bush rates, they would also reduce the difference between the two figures.