One of the most overlooked issues in the tax reform debate is whether the estate tax will survive. For advisors and insurance agents working with affluent married couples with $11 million of more in net worth, the ramifications could be dramatic.

Some affluent clients have purchased survivorship or second-to-die insurance policies to pay estate taxes when one spouse dies and the estate tax bill comes due. Depending on the final version of tax reform, it’s possible some clients may not need the insurance for estate tax purposes, but some advisors and accountants think some clients might still use it for income tax reasons as well as to maximize the size of the inheritance they leave behind.

Indeed, if the estate tax is abolished, that insurance could theoretically become unnecessary. Some observers of the high-net-worth world like Russ Alan Prince expect many wealthy people to try to unwind their survivorship insurance policies if that scenario materializes. The bigger the premiums they have left to pay, the greater the incentive to let the policies lapse. However, wealthier clients with more sophisticated advisors may try to convert the policies to private placement life insurance.

Like other aspects of tax reform, repeal of the estate tax is hardly guaranteed. And because it effects so few individuals, there has been virtually no conversation about it in Washington this year.

What discussion has surfaced has left serious estate planners perplexed. “They are talking about changing the estate tax but not the gift tax,” says one expert. “That doesn’t make any sense, but it also doesn’t mean it won’t happen.”

Frank Seneco, president of Seneco Global Advisors and Seneco & Associates in New Haven, Conn., thinks it is possible that the estate tax gets replaced with a version of the capital gains tax, leaving rich people with a lower blended tax rate. Still, clients could end up with a tax bill, albeit a smaller one, especially if they reside in states with an estate or inheritance tax.

A major question affecting second-to-die policies is whether there will be any changes to the marital exemption, currently at $5.49 million per person and $11 million for U.S. citizen married couples, as well as the unlimited marital deduction. “Changes to those exemptions could affect usage of second-to-die policies,” Seneco says.

Nothing is permanent, and when a new administration enters the White House in four or eight years, they could reinstate a repealed estate tax. Recall that the estate tax was gradually reduced in the previous decade and actually disappeared for a single year in 2010, only to return the next year.

So before cancelling a policy, clients need to consider the possibility of a disappearing and then reappearing death tax. Lisa Brown, principal at Brightworth, an RIA managing $1.5 billion in Atlanta, warns that clients  who let policies lapse now might find that they are uninsurable or far more expensive to insure four or eight years down the road.

Moreover, some small business owner clients may have purchased insurance to transfer the business or, in the case of family businesses in which some children are involved while others aren’t, to equalize the estate, giving company stock to those who will run the business and other assets to the rest. What happens in Washington won’t change those situations.