No, you claim either one or the other. If you are employed and have to use your vehicle to perform your work duties, it would generally be to your advantage to claim mileage tax relief as the HMRC's mileage allowance is generous enough to cover vehicle expenses such as fuel, maintenance and repairs, insurance, vehicle depreciation, etc. Claiming mileage tax relief is also a much easier process. However, if you choose to claim vehicle expenses rather than mileage allowance, bear in mind that you would only be able to claim the percentage allocated to business use i.e. If your car usage is split 20% business and 80% personal use, you can only claim back 20% of the vehicle expenses as tax relief. If in doubt, contact us so we can advise you on the best method to use.