I had a rocedure performed in Septmeber 1998. I got my bill in 1999, after the insuracne comanies haggled over who was primary vs. secondary. Can I receive reimbursement in 1999?

The regulations state that the expense must be incured during the plan year. I'm assuming from your question that your Flex plan year is a calendar year.If you had not already used up your 1998 election, most plans allow for a runout period after the plan year that allows participants to submit expenses that were incured during the plan year. It can vary from, but most commonly runs from 30 to 90 days. The runout can not be indefinite because the plan must file a 5500 form seven months after the plan year ends. Check your plan document to check the duration of your plan's runout.You can not use 1999 money to be reimbursed for a 1998 expense.