At Home or Office:
Most people will keep their documents at home or in their offices. The most important thing is to keep them SAFE so they will not get lost, stolen or damaged. You don’t want to be so clever in keeping the documents safe that no one can find them. You don’t want them where someone can walk off with your documents, especially a disgruntled or curious heir. You probably don’t want to store them where there is a chance of fire, water or other damage either.
A personal safe is a great idea but be sure that 1) it is not so small it can be stolen, or 2) the combination can be found by your Trustee. If you do not have a personal safe, you can store them high and out of the way but be sure your family knows where it is store. I tell people to take a selfie of themselves holding their plan documents in front of the place they will be stored. You can then send that image to your family so they know where to look and what to look for as well.
In a Safe Deposit Box:
This is a pretty safe place, right? It is in a bank after all. This can be a great location. During your life, in California, you can list access to your Safe Deposit Box on your power of attorney for asset management so that your Attorney-in-Fact can access the Box during your life. Some of these powers of attorney, though, are only on your incapacity and that may never happen. Remember, too, powers of attorney die with you so you need to provide access after you die as well. You can do this by adding someone else to your Box but then that may open a slew of other problems if that person cleans it out. You can list your Trust as owner of the Box or your Successor Trustee as having access to your Box so that when you are no longer Trustee, the Successor Trustee can access it. If it is in your name only, your family may need a court order to open up the box and remove your estate planning documents. Banks tend to be a little fussy about access to Safe Deposit Boxes. Imagine that!
With Your Estate Planning Attorney:
Even if you do either of the above options, your attorney should have a copy of the signed, notarized plan documents as well. I do not keep paper copies and tell clients that. I do keep electronic copies in .pdf and my original word processing format, along with all supporting documents, notes and e-mail. This is on a hard drive kept in a safe. That way, if the original documents are destroyed inadvertently, I can provide the back up copies that may be used to show your plan. The presumption of an intentionally destroyed original needs to be overcome first, however.
So, in short, the best plan is to keep the documents SAFE, whether safe in your home, in a safe or in a safe deposit box at your bank. The back up copy with the attorney has value but you should treat the originals as you would stock certificates or cash.