Churches that provide cell phones to pastors and staff members may find the perk an easier one to offer, thanks to a new federal law.

For years, employees who received cell phones as part of their work faced the tedious task of tracking each individual call in order to substantiate the business purpose of the calls and avoid taxes. Because such an effort proved challenging and time-consuming, many employers instead chose to offer cell phone allowances. The allowances removed the record-keeping burden, but they also resulted in taxable benefits for the employees who received them. That irked employees and irritated employers, since other office-related equipment—such as desktop phones or photocopiers—didn't require the same degree of documentation.

The new small-business tax relief likely will take many of these frustrations away. Beginning with the 2010 tax year, cell phones are no longer considered "listed property," meaning little documentation will be needed to prove their ...