A $50 change in the annual contribution limit for health savings accounts could end up costing employers and workers money if the IRS doesn’t come up with a quick fix, employer groups told Bloomberg Law.

The maximum contribution level of $6,900 for families in 2018 was reduced by the IRS to $6,850 in early March. The change was made because the Tax Cuts and Jobs Act required a move to the chained consumer price index to calculate inflation. The chained CPI is seen as a more accurate measure of inflation than the conventional CPI and it tends to suggest a...