If you expect to pass on millions of dollars to your spouse and kids, and re-evaluating your estate plan isn’t on the front burner, maybe this will light a fire under you.

Depending on how your will is worded, your spouse could end up with a smaller portion of your estate than you intended due to the new estate-tax rules, says Brad Dillon, a senior wealth planner at the New York office of Brown Brothers Harriman.

Here’s why: For wealthy people with wills drawn up before 2018, there’s a chance no specific dollar amount is stated for how much should go into a trust for the decedent’s children.

Instead, the will might refer to the “current federal estate-tax exemption amount” (or similar wording) that should be used in calculating the kids’ inheritance. The remainder of the estate — intended to be the larger portion — is then directed to a trust for the surviving spouse.

The looming complication: That exemption amount has doubled to about $11 million in 2018 from $5.49 million in 2017.

In other words, for a $12 million estate, that generic wording in the will means $11 million would go to the kids’ trust and $1 million to the spouse. And that may not be what you intended.

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