A savings account that is set up to pay qualified medical expenses of the account holder or a family member. It is used by employees who work for a small business, which is usually 50 employees or less, and contrasts with a Flexible Spending Plan, which is offered by large corporations. In order to use the Archer MSA, a company must have a high-deductible health plan. For medical expenses to qualify for payment from an Archer MSA, they generally must be unreimbursed and could be deducted on Schedule A of the 1040 Income Tax Return form.