I was not paid for some work I did as an independent contractor. How do I claim that loss?

[TBRN]

The company I worked for paid me for only part of the work I provided.  I invoiced them but they never paid me.  How do I claim the loss to offset the income? 

[Hal_Al]

You cannot claim that as a loss. But not having to report the income, you have effectively already "deducted" it.