The minimum, fundamental constituents, foundation, or support of a thing or a system without which the thing or system would cease to exist. In accounting, the value assigned to an asset that is sold or transferred so that it can be determined whether a gain or loss has resulted from the transaction. The amount that property is estimated to be worth at the time it is purchased, acquired, and received for tax purposes.
In a simple case, the basis of property for tax purposes under the Internal Revenue Code is the purchase price of a piece of property. For example, if a taxpayer purchases a parcel of land for $500,000, and no deductions apply to that parcel of land, the taxpayer's basis is $500,000. If the taxpayer later sells the property for $550,000, the amount of gain realized by the transaction is the sale price ($550,000) less the adjusted basis ($500,000), or $50,000.
Where a taxpayer is allowed to depreciate property with a limited useful life, such as an automobile used primarily for business purposes, the taxpayer's adjusted basis is reduced. Assume a taxpayer purchases an automobile for $30,000, and then claims deductions for $5,000. The adjusted basis of the automobile is then reduced to $25,000. When the taxpayer sells the automobile for $26,000, the amount of gain realized is $1,000 (the sale price of $26,000 minus the adjusted basis of $25,000).