When will we know what the tax forms for the year 2010 will look like? Looks like irs.gov doesn’t have them…
My income has altered by a large amount starting today, and I’d like to find out how this will change my tax amounts at the end of the year.
In the USA, we don’t pay taxes based on IRS forms. We pay taxes based on laws that Congress pass. Then, the IRS attempts to put those laws into tax forms. It’s the tax laws that the IRS enforce, not the tax forms.
The IRS doesn’t print the forms until the fall because there’s always the chance that the laws will change. In some cases, certain lines are based on circumstances (like inflation) that will not be known for many more months.
In short, just figure your taxes using this year’s forms and guess any changes that you know about (e.g. an increase in the standard deduction due to inflation).
Here’s a link to a site with some fairly confident predictions of next year’s taxes.
Note that inflation is extremely low this year, and the personal exemption and standard deduction are not expected to change much, if at all.
Congress passes laws throughout the year that affect both the tax you pay and the IRS forms. In fact, it’s not unusual for laws to be passed so late in December that the IRS doesn’t even have a form for it until February or March. This is one of my MAJOR pet peeves. Congress should not be able to pass new tax legislation after the end of October, as far as I’m concerned.
(Just as one example of how late changes might be passed… a law passed in January 2010 regarding donations for Haiti relief permitted a deduction on your 2009 income tax. So… by summer of 2011, we’ll know for sure what the final tax laws are for 2010. 
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