From the IRS website:Question: For business travel, are there limits on the amounts deductible for meals?
- Meal expenses are deductible if your business trip is overnight or long enough that you need to stop for substantial sleep or rest to properly perform your duties. Meal expenses are also deductible if the meal is business-related entertainment. You can figure all your travel meal expenses using either of the following methods:
- Actual cost. If you use this method, you must keep records of your actual cost.
- The standard meal allowance, which is the federal meals and incidental expense (M&IE) per diem rate. The GSA website lists these rates by location. Note that lower rates apply for the first and last days of travel.
- The deduction for unreimbursed business meals is generally subject to a 50% limitation.
The per diem expenses you wish to claim should be treated as Meal Expenses in TurboTax, which will then automatically apply the 50% reduction (you are only allowed to deduct 50% of your meal expenses).
As long as you have good records and can substantiate your travel days and location, you should not have any problems, even if the IRS does question the expense.