The phone as a business expense seems obvious. After all, communicating with customers, suppliers, potential customers or arranging matters over the phone in the office is the everyday life of every company. However, when it comes to tax deduction of telephone costs, the matter is more complex. Self Employed The cost of deducting the phone in the case of self employed is quite simply. 1. Having two mobiles, we designate one that we use for business purposes and the cost of th