You may reduce the chance of making arithmetic errors on your tax return by rounding off amounts to the nearest dollar, the Internal Revenue Service says.
When you round off one dollar item, however, you must consistently round off all amounts. Amounts under 50 cents should be dropped. For example, $19.21 becomes $19.00. Amounts from 50 cents to 99 cents should be increased to the next higher dollar, so $19.50 becomes $20.00. If you do round off, do so for all amounts. However, if you have to add two or more amounts together to figure the total to enter on a line, include cents when adding the amounts and only round off the total.