Question 13 of 30. Kelsey (31) contributed $250 per month to a self-only health savings account (HSA) through her paycheck in 2018. Her employer contributed $500 per year, Kelsey contributed $300 of her Christmas bonus into her HSA on January 5, 2019, an after-tax contribution for 2018 Kelsey's excess contribution amount is and the excise tax is $500; $100 $400; $24 $350; $21 $300; $18 Mark for follow up