A health savings account (HSA) is a type of savings account that sets funds aside for health-related expenses. HSAs are similar to FSAs but are limited to people with high-deductible health plans. Account holders fund their HSAs by withholding a portion of their pre-tax paycheck or by making a direct tax-deductible contribution at any time. HSA funds do not expire and roll over year to year if the funds are not spent. Also, HSAs can be placed in an investment fund and grow tax-free over time.