08/11/2026
Expense Deduction Rules for Personal Property Used for Business – Did You Know?
Many self-employed people may qualify to reduce their taxable income by deducting business expenses. In general, you must allocate expenses related to mixed-use property based on your "percentage of business use." But how is this percentage calculated?
For many types of equipment, your business use percentage may be based on a reasonable measure such as time or output. For example, if you use your computer for 30 hours a week in your freelance work and 20 hours a week for personal purposes (total of 50 hours), then your business use percentage would generally be 30/50 = 60%. Meanwhile, if you have a printer and print 400 pages for business reasons and 100 pages for personal reasons (500 pages total), then your business use percentage would typically be 400/500 = 80%. Therefore, you could generally allocate 80% of shared costs like ink and paper to business use.
On the other hand, business percentages for vehicles should be based on mileage, not time. So if you drive your car 4,500 miles this year in the course of your self-employment work, and 10,500 miles for all other purposes (total of 15,000 miles), then your business use percentage would be 4,500/15,000 = 30%. Alternatively, if eligible, you may choose to use the standard mileage rate and calculate your vehicle deduction based on your qualifying business miles instead of deducting your share of actual vehicle expenses. Be sure to keep records that support your business use percentage, such as mileage logs, usage records, or other documentation showing how the property was used for business and personal purposes.