“The first six months of 2012 I was able to deduct all my mileage. The last six months I have been given a car allowance ($550) taxed and a .2775 per mile reimbursement. Can I deduct the balance of the mileage?”================>As you you received a car allowance from your ER, the IRS considers that to be reimbursement of your business expense. If your car allowance equals your car expenses, you have nothing to deduct. But as you can verify that your car expenses exceeded the car allowance from your employer, you can deduct the unreimbursed difference as a miscellaneous deduction on Sch A of 1040, subject to the 2 percent income exclusion. That means you add together your unreimbursed EEcar expenses and your other miscellaneous deductible items, and deduct the amount that exceeds 2 percent of your AGI.You can use the IRS standard mileage rate, which was 55.5 cents per mile as of 2012, to figure your car expenses. You must keep records of the miles driven for business purposes and multiply your business miles by 50 cents to arrive at your business-related operating expenses. So, since your employer’s car allowance is less then the IRS standard rate, you can deduct the difference. For instance, if your employer allows .2775 cents per mile, you can deduct the .2725 cent-per-mile difference from the 55.5-cent standard rate as an unreimbursed EE business expense.
“ If so, how. I have successfully used HR Block for years, but am unable to figure this out. HR Block assistance isn't very good.”===========>As said above, report it on Sch A of 1040 line 21 subject to 2% of AGI.So UNLESS you itemize your deductions on your return, you can’t claim the bal of the mileage.