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Well-to-do households are likely to keep their millions in the family for a long, long, time, courtesy of the GOP's proposed tax bills. Bills from both House and Senate Republicans call for an immediate increase in the amount of assets you can pass on without being subject to the federal estate tax. And because of how the bills were written, inheritors can escape most, if not all taxes. Currently, an individual can transfer up to $5.49 million in assets free of estate taxes. Amounts over that are subject to a top levy of 40 percent. Some 11,310 estate tax returns are expected to be filed in 2017, and about half of them will be subject to the tax, according to estimates from the Tax Policy Center. The Senate bill permits individuals who die in 2018 to leave up to $10 million in assets, effectively doubling the amount the wealthy can transfer. The House bill goes a step further, also doubling the amount that can be transferred tax-free and ultimately ending the estate tax altogether. Under the House version, the estate tax will disappear on Dec. 31, 2024. Watch: White House economic advisor Gary Cohn says estate tax helps a "lot of different people"

And here's where that twist comes into play: Heirs who want to immediately sell off assets they inherit will also save on capital gains taxes. Both proposals keep the so-called step-up in basis, meaning future generations inherit assets at their current market value and not at the price the giver initially paid. Here's how that would work: Let's say Dad bought 100 shares of company X at $10 a share. When he dies, it's now worth $50 a share. If the heir or heirs decide to immediately sell the holding, none of the gain would be subject to capital gains taxes. Eliminating the estate tax while keeping the step-up has been floated before in Congress, but those proposals never went far. "It's a surprise to see this resurface with no estate tax and the preservation of the step-up," said Charlie Douglas, director of wealth planning at Cedar Rowe Partners in Atlanta. Here are the moves well-to-do households may make to ensure they keep their cash all in the family.

Changing of the guard

With the 2018 midterms and 2020 elections not all that far away, some tax experts believe that the rules could change and become less generous toward wealthy families. The well-to-do can try to shield their wealth and their descendants from any future changes by transferring their assets to dynasty trusts. Drafted properly, a dynasty trust allows you to parcel out assets to future generations — including grandchildren and great-grandchildren — without subjecting the recipients to estate taxes. Descendants also enjoy the asset's appreciation in value over time. "If another administration comes in three years from now, everything can change," said Douglas of Cedar Rowe Partners. "Truly wealthy families will pack as much as they can into dynasty trusts."

Less gifting, more holding

Gifting may become less desirable with a higher estate tax exemption and the step-up in basis. Each person is entitled to give away up to $5.49 million in assets, tax-free. This is the same exemption that applies to the estate tax. You can also make tax-free gifts of up to $14,000 a year ($15,000 in 2018) without eating into your lifetime gift exemption. Under current law, recipients of gifts get the donor's adjusted basis — they don't get a step-up. This means that if the recipient sells the asset immediately, he or she may be subject to large capital gains taxes if the asset went up sharply in value.

Step up vs. no step up Sale price per share Cost basis Capital gain per share Tax per share Step up $40 $40 $0 $0 No step up $40 $2 $38 $7.6