For 2009, qualified individuals with small businesses may be eligible to make smaller estimated tax payments. If you qualify, your required annual payment for 2009 is the smaller of 90% of the tax shown on your 2008 tax return or 90% of the tax shown on your 2009 tax return. You must check box F in Part II on Form 2210 or box C on Form 2210-F to certify that you qualify.
You are a qualified individual if:
More than 50% of your gross income was from a business that had an average of fewer than 500 employees in 2008, and
Your adjusted gross income in 2008 was less than $500,000 ($250,000 if you are filing married filing separately for 2009).