In most cases, you must pay estimated tax for 2010 if both of the following apply.
1. You expect to owe at least $1000 in tax for 2010, after subtracting you withholding and refundable credits. 2. You expect your withholding and refundable credits to be the less than the smaller of: a) 90% of the tax shown on your 2010 tax return, or b) 100% of the tax shown on your 2009 tax return. Your 2009 tax return must cover all twelve months.
