You can contribute to your HSA any time of the year, up to the annual limit. For 2018, the limits are $3,450 for a plan that covers one person, and $6,900 for a plan that covers more than one person.

Ways to contribute include:

• Have a set amount taken out of your paycheck each week before taxes
• Deposit money that’s already been taxed—you can deduct it from your income on your tax return, no matter who it came from
• Your employer can put money into your HSA and save on taxes, too
• Invest the funds in your HSA to earn interest; a minimum account balance may be required
• You can move money from an IRA to your HSA once—called a one-time rollover

Publication 969 from the IRS will give you more information about making contributions.