Deducting Commuting Costs
You can’t deduct the cost of transporting tools, equipment or other materials by car if you would normally have commuted in the car. If you regularly take mass transit to work, you can deduct the additional cost of transportation.
For example, an electrician who takes his tools to a work site was allowed to deduct car expenses, since he usually used public transportation. (Grayson, TC Memo 1977-304).
Similarly, a taxpayer was allowed to deduct the excess cost of carrying tools in a pickup truck when his passenger car would not have been able to withstand the extra weight. (Poll, TC Memo 1977-20).