If you are an employee who receives a W-2 you cannot deduct any employee business expenses due to the tax code changes in effect for tax years 2018 thru 2025.

---

@DoninGA wrote:

If you are an employee who receives a W-2 you cannot deduct any employee business expenses due to the tax code changes in effect for tax years 2018 thru 2025.

---

Your employer can reimburse you tax-free if they use an accountable plan (where you prove expenses with receipts).  In some states, state labor laws may place limits on the ability of an employer to require you to work in a way that forces you to incur unreimbursed expenses.  You should discuss reimbursement of your legitimate business expenses with your employer, and then possibly check with your state labor board. 

If your employer gives you a fixed "allowance" for expenses, for example $200/month for "gas" , the IRS code requires that to be treated as taxable income to you.  However, if they reimburse you for actual expenses (an accountable plan), that reimbursement is not taxable.  The common example of an accountable plan: you submit an expense report, to your employer, for  of the amount  of business miles you drove  and they pay you the IRS mileage rate, for those miles.