Businesses should be mindful of a few important tax law changes and extensions for 2009.

Bonus depreciation—The 50% bonus first-year depreciation deduction rate is extended for the 2009 tax year. Qualified property or equipment purchases must have been placed into service before January 1, 2010.

Section 179 expensing—The $250,000 deduction for depreciable assets such as manufacturing equipment, office computers, and furniture is extended for the 2009 tax year.

Net operating loss carryback—As in 2008, businesses can carry back a net operating loss from 2009 to the previous three, four, or five years, instead of the usual two years.

Capital gains tax break—75% of capital gains earned from investments in small businesses in 2009 or 2010 can be excluded from taxation if the investment is held for five years.

Vehicle sales tax holiday—State sales taxes paid on any new vehicles purchased between February 16, 2009, and January 1, 2010, are fully tax deductible on the first $49,500 in cost.

Work opportunity tax credits—Tax credits worth up to $2,400 per hired worker are awarded to businesses that hire certain unemployed veterans and those under 25 who’ve been out of school for six months or more.

COBRA premium assistance credit—If your business laid off workers in 2009 who are now paying into the COBRA program to continue their health care coverage, your business could be in line to receive a rebate from the federal government for the 65% of the premium cost not being paid by the individual. However, reimbursements are available for only nine months.