You are covered under a high deductible health plan (HDHP), described later, on the first day of the month. You have no other health coverage except what is permitted under Other health coverage, later. You aren't enrolled in Medicare. You can't be claimed as a dependent on someone else's tax return. For exceptions and details see IRS Publication 969. Deposits to a health savings accounts may be made by any policyholder of an HSA-eligible high-deductible health plan, by the employer, or any other person. If an employer makes deposits to such a plan on behalf of its employees, all employees must be treated equally, which is known as the non-discrimination rules. If contributions are made by a Section 125 plan, non-discrimination rules do not apply. Employers may treat full-time and part-time employees differently, and employers may treat individual and family participants differently; the treatment of employees who are not enrolled in a HSA-eligible high-deductible plan is not considered for non-discrimination purposes. As of 2007, employers may contribute more for non-highly compensated employees than highly compensated employees. Contributions from an employer or employee may be made on a pretax basis by an employer. If that option is not available through the employer, contributions may be made on a post-tax basis and then used to decrease gross taxable income on the following year's Form 1040. Employer pre-tax contributions are not subject to Federal Insurance Contributions Act tax or Medicare taxes, but employee pre-tax contributions not made under cafeteria plans are subject to FICA and Medicare taxes. Regardless of the method or tax savings associated with the deposit, the deposits may only be made for persons covered under an HSA-eligible high-deductible plan, with no other coverage beyond certain qualified additional coverage. Initially, the annual maximum deposit to a health savings account was the lesser of the actual deductible or specified Internal Revenue Service limits. Congress later abolished the limit based on the deductible and set statutory limits for maximum contributions. All contributions to a health savings account, regardless of source, count toward the annual maximum. A catch-up provision also applies for plan participants who are age 55 or over, allowing the IRS limit to be increased. This "catch up" contribution limit was set to $500 for 2004, increasing $100 each year until it reached a maximum of $1,000 in 2009. For 2019, the contribution limit was $3,500 for single or $7,000 for married