Can I take a deduction for sale of property (residential lot never built on) at a loss?

[DoninGA]

The sale of personal residential property, not used as an investment or in a business, for less than the purchase price is not reported on a tax return.

[Hal_Al]

As the other answer indicates, you may not deduct a capital loss on the sale of personal use property such as a 2nd home or vacation home. 

I'm of the opinion that most vacant land can be treated as investment property, even a residential lot that you purchased for the purpose of building a 2nd (or primary) home; as long as the property was not actually used for personal use (e.g. camp site, gardening, playground). 

[AmeliesUncle]

The Courts usually look at intent.  If the vacant land was intended for personal use, the loss is non-deductible.  If it was intended for investment or business purposes, the loss is deductible.