You should review your estate plan every 3-5 years at minimum, and immediately after any major life event.
Events that should trigger a review:
Marriage or divorce. Birth or adoption of a child or grandchild. Death of a spouse, beneficiary, or executor. Significant changes in financial situation (inheritance, business sale, retirement). Moving to a different state (estate laws vary significantly). Changes in tax laws that affect estate planning. A beneficiary developing special needs or financial problems. Changes in your relationship with beneficiaries or fiduciaries.
What to review:
Beneficiary designations: These on retirement accounts and life insurance override your will — make sure they're current.
Executor and trustees: Ensure the people you've named are still willing, able, and appropriate.
Guardians: If you have minor children, confirm your chosen guardians are still the right choice.
Powers of attorney: Make sure your designated agents are current.
Trust funding: Verify that assets you've acquired since the last review have been properly titled in the trust's name.
A periodic review with your estate planning attorney is one of the most important things you can do to ensure your wishes are carried out.