Having an estate plan is important, but having one means only part of your job is done. A plan has to be complete and current. Not enough people have an estate plan, but of those that do a high percentage let their plans become outdated. Sometimes having a plan that isn’t current is worse than not having a plan at all.

Your estate planner probably prefers that you touch base every year or two. There’s something to be said for that guideline, but it’s too much for a lot of people. They don’t want to spend that much time and money on estate planning. There’s a middle ground between that approach and the set-it-and-forget-it model.

There are five questions you should ask every few months. The answers tell you when it’s time to visit your estate planner.

Do I still have the right people in charge? In the past I’ve written that the wrong executors or trustees can foil even the best estate plan. The agents who can act for you under either a financial or medical power of attorney also are critical choices.

Review the choices in your plan. Especially if your plan has been in the file a few years, the choice might not be ideal today. Perhaps the reliable relative, friend, professional, or employee you selected has different circumstances. People grow older, move, take on too many other capacities, or have a number of other changes in their lives. Your contacts with a person might not be as frequent as they once were, so the person isn’t as familiar with matters. Or perhaps your estate has changed in ways that make your original choice unsuitable. Maybe your estate is larger or more complicated than it was.

The executor, trustee, and agents are the keys to ensuring your plan is implemented as you intended. Keep in touch with them and regularly reconsider their selection. When you think a change might be in order, talk with your estate planner.

What’s changed in your life? Major changes in your life are the most frequent reason that a visit to the estate planner is in order. Marriage and divorce are the big changes, and your state law might automatically invalidate all or part of your will if your marital status changed.

But there are a host of other changes that are critical. Your plan might need to be revised if you have new children or if children grew into adulthood. The introduction of a grandchild or changes in a grandchild’s life also might alter your will. Changes in your health or the health or a loved one also might require changes.

Perhaps your net worth is different than anticipated in your current plan, in either a positive or negative way. Or the structure or your assets or liabilities has changed. Maybe you started or sold a business or investment real estate. Or you own different types of investments. You could have new or different charitable interests. Over a few years, small, gradual changes that we take in stride could compound to make your situation very different from the one contemplated in your plan.

Some of these changes require only a small change, such as a codicil (amendment) to the will that includes a new grandchild. Others require you to reconsider all or significant provisions of your plan.

Where are you spending time? Each state has its own laws governing estates, trusts, property ownership, and powers of attorney. In general, the state in which you are considered to be a resident or domicile is the state where your will is probated and that governs your trusts and financial power of attorney. The medical power of attorney and related documents has to be valid in the state you’re physically in when medical care is needed. Of course, states have different tax laws, and a plan that make tax-sense in one state might not be wise in another.

Your estate planner needs to know if you moved or are spending more time out of state than you used to (perhaps spending winter or summer in a more hospitable climate).

Discuss your travels and residence with an estate planner. The planner will determine which state is considered your current legal residence. The planner also might recommend relatively small changes that can establish your residence in the more desirable state for your estate. You also need to avoid the very undesirable position of being considered a legal resident of two states.

Where is your property? Real estate is subject to probate and related laws in the state in which it is located, regardless of where the owner lives. Some other property also might fall under the laws of another state instead of your home state.

If you bought property in another state, your estate will have to go through probate in at least two states. There are ways to avoid this expensive situation. Your planner might recommend putting the out-of-state property in a trust or limited liability company or some other strategy. Purchasing property or a business that’s located in another state should trigger a visit to your planner.

How old is your plan? I’ve already listed life changes that should trigger a review of your estate plan. But there are other events, some of which you might not even aware of, that make your plan obsolete.

There’s the federal tax law, of course. Your state law also can change. Many states have been revising their probate and trust laws in recent years. Changes in Medicare and other seemingly unrelated laws and programs could affect your estate plan.

In addition, estate planners always are refining their strategies and finding better ways to do things. An example is in the standard trust. It used to be commonplace for a surviving spouse or other primary beneficiary to receive only the income earned by the trust. Principal and capital gains were reserved for the next generation or two. But with today’s low interest rates, income doesn’t amount to much. Most trusts drafted now pay the first generation beneficiary a fixed percentage of the trust or a dollar amount annually without regard to whether it is paid from income, capital gains, or principal.

Most laypeople aren’t aware of all the changes that make revising your plan a good idea. A general rule is that if your plan is more than five years old, you probably should touch base with your planner. When your plan is more than 10 years old, you definitely need it reviewed.

The problems caused by an out-of-date estate plan all will be resolved if you don’t revise the plan. But the courts will resolve them. This will cost your estate money and delay the resolution. And the resolution might not be anything like what you would have preferred.