Yes, you can deduct per diem or actual job related expenses, like meals, lodging, air fare, cabs, dry cleaning, etc., if your assignment away
from your main workplace is temporary (expected to last, and does last, for one
year or less). If your assignment is indefinite
(expected to last for more than one year) then your new workplace becomes your
tax home and you cannot deduct your job related expenses.
If you are a Department of Transportation (DOT) worker, click on: What does "You are in the transportation industry" mean? and Where do I enter my Department of Transportation (DOT) per diem?
The amount claimed must be reduced by any amount that is reimbursed by the employer.
If you are an employee, your allowable travel expenses are figured on Form 2106 or Form 2106-EZ. Your allowable unreimbursed expenses are carried from Form 2106 or Form 2106-EZ to Form 1040, Schedule A (PDF), and are subject to a limit based on 2% of adjusted gross income. Refer to Topic 508 for information on the 2% limit. If you do not itemize your deductions, you cannot deduct these expenses.
To enter your Job Related Expenses, click on
Where do I enter job-related employee expenses? (Form 2106)
Additional information :
https://www.irs.gov/taxtopics/tc511.html
