Definition of Materiality
In accounting, materiality refers to the relative size of an amount. Relatively large amounts are material, while relatively small amounts are not material (or immaterial). Determining materiality requires professional judgement. For instance, a $20,000 amount will likely be immaterial for a large corporation with a net income of $900,000. However, the same $20,000 amount will be material for a small corporation with a net income of $40,000.
Another view of materiality is whether sophisticated investors would be misled if the amount was omitted or misclassified. If sophisticated investors would be misled or would have made a different decision, the amount is considered to be material. If sophisticated investors would not be misled or would not have made a different decision, the amount is judged to be immaterial.
Example of Materiality
A classic example of the materiality concept is a company expensing a $20 wastebasket in the year it is acquired instead of depreciating it over its useful life of 10 years. The matching principle directs you to record the wastebasket as an asset and then report depreciation expense of $2 a year for 10 years. Materiality allows you to expense the entire $20 cost in the year it is acquired. The reason is that no investor, creditor , or other interested party would be misled by immediately expensing the $20 wastebasket.
Materiality also justifies large corporations having a policy of immediately expensing assets having a cost of less than $2,500 instead of setting up fixed asset records and depreciating those assets over their useful lives.