Amounts that you put into a flexible spending account through work aren't tax deductible. Instead, your allocations are withheld pretax by your employer. This means you get the tax break up front rather than on your individual return.
Flexible Spending Basics
To participate in a flexible spending program through your employer, you enroll and report your desired allocation. You don't have to take the full benefit allowance, which stands at $2,550 in 2015. However, people who regularly use medical, dental and vision care services often make use of the full amount. Your total allocation is divided across all annual paychecks, and an amount is withheld pretax.
Even though you pay into the account in installments, you can use the full allocation throughout the year for basic co-payments, deductibles, dental care and other medical expenses outlined in your provider's manual.
Making use of a flexible spending account enables more people to get a tax break on medical expenses than can get them through the traditional deduction route. To take deductions on your annual income tax return, your medical expenses must exceed 7.5 percent of adjustable gross income as of 2015. With a flexible spending account, you get a tax break on up to $2,550 of medical expenses regardless of income.