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If you plan on leaving a sizable amount of money to your heirs, it's understandable to be concerned about estate taxes. After all, the top Federal estate tax rate of 40% could take a nasty bite out of a multi-million dollar estate, and that's not including any state taxes that may apply. With that in mind, here are three suggestions from our contributors that could help you lower the estate tax's burden on your loved ones.

Matt Frankel: The estate tax only applies to amounts left to heirs in excess of the lifetime basic exclusion amount, which is $5.43 million for 2015. This includes all taxable gifts given during the person's lifetime. For example, if a wealthy individual dies and leaves an estate worth $10 million to heirs, the amount subject to taxation is $10,000,000-$5,430,000 = $4,570,000.

However, thanks to the annual gift exclusion, which currently stands at $14,000 per person, it is possible for individuals to pass some of their estate on to heirs, tax free, while they're still alive. In other words, in order to reduce the total value of the estate, a wealthy person could start giving his/her money away to heirs every year.

Let's say that same individual with a $10 million estate decides to get proactive about estate planning. We'll assume this person has three children (all of whom are married) and a total of eight grandchildren. Each year, they could give $14,000 to each of these heirs and their spouses for a total of $196,000 in tax-free gifts each year. Over a period of several years or even decades, you can imagine how this could put a nice dent in the eventual estate tax liability.

Dan Caplinger: Your home is often your biggest asset, and being able to reduce the amount of estate tax you pay on your home can be a huge money-saver for your family. A strategy using what's known as a Qualified Personal Residence Trust, or QPRT, can help you achieve this key goal in your estate planning.

To use the QPRT strategy, you transfer your home into a trust under which you pick how long the trust will last and who will receive your home when the trust ends. The QPRT allows you to keep living in your home throughout the period you set, and while you still have to pay real-estate taxes and insurance, you also get the income-tax benefits of home ownership. After the trust terminates, you can generally still live in your home, but you'll have to pay fair-market rent to the beneficiaries going forward.

The key is that for gift tax purposes, the value of the home is discounted to reflect the delay in the gift to the trust beneficiaries. The longer the term, the greater the discount. However, if you die before the trust ends, you undo many of the benefits, and so you shouldn't simply pick an extremely long term.

The QPRT is a highly specialized strategy, but it's one that many families should consider. If you have a taxable estate and much of your net worth is in your home, a QPRT could be your best option to cut your taxes.

Sean Williams: I've said it before and I'll say it again: Where you live can make a big difference when it comes to how much you pay in taxes, and how much of your wealth ultimately gets transferred to your beneficiaries.

My Foolish colleagues have offered two great ideas here to lower your estate taxes. As for me, I'm going to suggest you take a good look at where you plan to retire, as the state you live in could bear an estate tax that could reduce the value of your estate.

Currently, there are 15 states, along with the District of Columbia, that have an estate tax. As you might imagine, each state can have a different minimum and maximum tax, as well as differing exemption thresholds. For example, Hawaii's and Delaware's state exemption matches the federal government at $5.43 million. On the other side of the coin, New Jersey only exempts the first $675,000 of an estate, meaning many New Jersey residents will see their estate reduced by taxation.

Additionally, Washington State has the highest maximum estate tax rate of 20%, and the highest minimum estate tax rate of 10%. For the majority of the 15 states that do have an estate tax, it often ranges from a low of 0.8% to a maximum of 16%.

I suggest to take some extra time to understand how taxes could affect you during your golden years and once you pass. If you live in one of the 35 states that doesn't have an estate tax, then focusing on some of the suggestions offered by my colleagues could help you lower your estate tax liability to the federal government. If you do live in one of the 15 states with an estate tax, be aware of what sort of liability your estate could face down the road.