What is a "Codicil"?

If you already have a will but want to make a change, you may be wondering whether you need to start from scratch. A “codicil” is one way to update an existing will without rewriting the entire document. Used correctly, a codicil can make targeted updates—like changing an executor, adding a new beneficiary, or adjusting a specific gift. Used carelessly, it can create confusion, invite disputes, or even be rejected by a court.

This article explains what a codicil is, when it might make sense to use one, how state-law formalities affect validity, and how codicils show up in probate. Laws vary by state and the details matter, so consider this a general overview rather than a substitute for legal advice about your specific situation. For related guidance, see What is a "Self-Proving Affidavit"?.

What Is a Codicil? A Plain-English Definition

A codicil is a separate legal document that amends an existing will. Instead of replacing your will, a codicil changes particular sections—such as who serves as executor (also called a personal representative), who receives a specific bequest, or how a piece of property is distributed. When properly signed and executed according to state law, the codicil and the will work together. The will remains in place, and the codicil overrides or adds to parts of it. For related guidance, see Does a will have to be notarized to be probated?.

Think of a codicil as a controlled edit rather than a full rewrite. It points to the original will by date, identifies the sections being updated, and makes the new terms clear. If there is ever a conflict between the will and the codicil, the codicil generally governs on the points it addresses.

When to Use a Codicil vs. Writing a New Will

Whether a codicil is appropriate depends on the type and number of changes you want to make, how complex your estate has become, and how clear your original will is. Here are practical guidelines:

Consider a codicil when making a narrow change. Common examples include updating your executor or successor executor, changing a specific bequest (for example, giving a particular item to a different person), or correcting a misspelling or outdated address.
Consider a new will when changes are broad or layered. If you want to change multiple gifts, rearrange the overall distribution plan, add complex provisions (like contingent gifts or trust terms), or revoke many parts of your will, a clean replacement will is often clearer and reduces the risk of conflicts between documents.
Consider a new will when your life has changed significantly. A marriage, divorce, birth or adoption, major change in assets, or a move to another state often warrants a fresh, comprehensive will so everything fits together under current law.
Consider a new will if the original will is outdated or poorly drafted. If the base document is unclear, adding a codicil can compound confusion. A new, integrated will may be the more reliable path.

There is no one-size-fits-all answer. The key is clarity. The simpler and more consistent the set of documents, the easier they are to carry out and defend in probate.

Formalities and Validity: Why State Law Matters

Codicils must meet the same (or very similar) formal signing requirements as wills, and those requirements differ by state. This can include the number of witnesses, who can serve as a witness, whether a notary is required for certain affidavits, and the exact language recommended for self-proving documents. Some states recognize handwritten (holographic) wills or codicils under specific conditions; others do not.

Key points to keep in mind:

Witnesses. Many states require two witnesses who observe the signing and the testator's acknowledgment. Some states limit who can witness (for example, people who are not beneficiaries).
Notarization and self-proving affidavits. While notarization may not be strictly required to create a valid will or codicil, a notarized self-proving affidavit can streamline probate by allowing the document to be accepted without witness testimony. Rules vary by state.
Capacity and voluntariness. The person making the codicil must have testamentary capacity and act without undue influence. Disputes commonly target these issues.
Physical attachment vs. reference. Stapling or attaching a codicil to a will is not what makes it legally effective. The codicil should clearly refer to the will by date and be executed correctly. Altering the will with handwritten notes, strikeouts, or sticky notes can cause problems.
Multiple codicils. If you make several codicils, conflicts can arise about which provisions control. Some states expect later codicils to reaffirm earlier ones unless expressly revoked. Others scrutinize overlapping clauses closely.

Because each state has specific requirements, a codicil that would be recognized in one state could be questioned in another. If you have moved states or own property in multiple states, the stakes can be higher. Laws vary by state, and a small misstep in execution can jeopardize the document's validity.

Considering changes to your will? To discuss hiring counsel to prepare or review a codicil—or to evaluate whether a new will is the better approach—speak with our firm about representation. Use our contact form or call 414-253-8500 to schedule a consultation and talk through next steps.

How Codicils Affect Probate and the Personal Representative's Duties

When someone passes away, the original will is typically filed with the probate court. If codicils exist, they must also be filed. The court and the personal representative (also called the executor) then read the will and codicils together as a single plan. Here is how codicils can affect the process:

Proving the documents. The court needs to be satisfied that each codicil was executed in compliance with state law. If a self-proving affidavit is present and acceptable under the state's rules, that can streamline admission. If not, witnesses may have to provide statements or testimony.
Determining controlling terms. The personal representative must apply the most recent valid terms. A later codicil typically overrides earlier will provisions on the same topic, but care is needed to reconcile multiple documents and avoid misreading legacy clauses.
Asset distribution and sequencing. Codicils may create or remove specific gifts, which can change how residuary assets are calculated. This matters for paying creditors and expenses, then distributing what remains according to the combined documents.
Notices to beneficiaries. If beneficiaries change, the personal representative's notice obligations can change too. The personal representative needs an accurate list of all current beneficiaries as updated by any codicils.
Potential for disputes. Heirs or beneficiaries might challenge a codicil on grounds of undue influence, lack of capacity, or improper witnessing. The more codicils there are—and the more they conflict with the original plan—the more likely questions may arise.
Locating originals. Courts typically expect an original signed codicil. If only copies are available, the personal representative may need to follow state-specific procedures to have a copy accepted, if permitted.

For personal representatives, verifying that you have every codicil and understanding how they interact with the will is an early, critical task. Missing a codicil or misreading its effect can lead to downstream issues with filings, creditor payments, or distributions.

Common Mistakes and Risks to Avoid

Because codicils modify an existing legal document, even small drafting or signing errors can cause outsized problems. Frequent pitfalls include:

Marking up the will by hand. Scratching out names or writing notes in the margins is rarely effective and can invalidate parts of the will. Use a properly executed codicil or a new will.
Failing to follow witness rules. Using a beneficiary as a witness, missing a witness entirely, or having witnesses sign at different times can expose the codicil to challenges under state law.
Stacking multiple codicils. Over time, several codicils can contradict each other or make the plan hard to read. At that point, drafting a new will is often cleaner and reduces ambiguity.
Vague references. A codicil should clearly identify the will it amends (by date) and specify exactly what changes. Ambiguity invites disputes.
Ignoring non-probate assets. Codicils affect your will, but not beneficiary designations on assets like life insurance, retirement accounts, and payable-on-death accounts. Align these designations with your updated plan.
Not addressing guardians or trusts consistently. If your will includes guardianship provisions or testamentary trusts, changes to beneficiaries or distributions should be coordinated so the terms remain workable.
Misplacing originals. A codicil that cannot be located may be treated as revoked or may require extra steps in probate. Keep documents organized and accessible.

Practical Next Steps to Update Your Estate Plan

1) Identify exactly what needs to change

Write down the parts of your current will that no longer fit: executor, specific gifts, percentages, guardianship, or trust terms. Note any new beneficiaries or changed circumstances. If your will is older, consider whether your overall plan—not just one clause—needs an update.

2) Gather your current documents

Locate the most recent signed original will and any prior codicils. If you have moved states since signing, flag that. Note where you have beneficiary designations outside the will (retirement accounts, life insurance, bank accounts) so the entire plan can be reviewed together.

3) Decide between a codicil and a new will

As a rule of thumb, one or two targeted edits may be right for a codicil; multiple or structural changes often call for a new will. When in doubt, prioritize clarity and simplicity to reduce risk in probate.

4) Ensure proper execution under your state's rules

State law governs witness requirements, notary use, and acceptable language for self-proving affidavits. Following the correct process can make probate smoother and reduce the risk of a contest. Laws vary by state, so do not assume the rules are the same everywhere.

5) Keep the original secure and inform key people

Store the original codicil with your original will in a safe, accessible place. Tell your named personal representative where the originals are kept. Consider providing copies to relevant parties, but protect your privacy and the integrity of the originals.

6) Review the whole estate plan periodically

Life changes. Periodic reviews help ensure your will, codicils (if any), beneficiary designations, powers of attorney, and other planning documents work together and reflect your current wishes.

Short Examples: When a Codicil Can Make Sense

Updating an executor. You want to replace your initial executor with a trusted alternate. A codicil that clearly states the change can be efficient.
Adjusting a specific gift. You promised a family heirloom to a different person or want to add a small charitable bequest. A narrow codicil may be sufficient.
Correcting a clerical error. A misspelled name or outdated address can be addressed through a focused codicil.

By contrast, if you are changing multiple beneficiaries, altering percentages across the board, or restructuring a trust, drafting a new will usually provides a cleaner, more reliable framework.

Considerations for Executors and Personal Representatives

If you are serving as a personal representative and discover one or more codicils:

File all originals with the court as required. The court must see the full testamentary set: the will plus any codicils.
Confirm the latest controlling terms. Read each codicil carefully to determine how it alters the will. Create a consolidated summary to guide notices, asset marshaling, creditor payments, and distributions.
Track deadlines. Probate often involves prompt filings, creditor notice periods, inventories, and accountings. The presence of codicils does not stop the clock.
Prepare for questions from beneficiaries and creditors. Codicils can change who is entitled to what. Clear communication and accurate documentation reduce misunderstandings.
Seek guidance if there is a dispute or missing original. If a beneficiary contests a codicil or an original cannot be located, state-specific procedures may apply to resolve the issue.

Frequently Asked Questions About Codicils

Can I handwrite a codicil, and will it be valid?

Some states recognize handwritten (holographic) wills or codicils if strict conditions are met, while others do not. Even where allowed, handwritten documents are more likely to be challenged because they often lack witness signatures or clear language. Typed, properly witnessed documents generally reduce risk. Laws vary by state.

Do codicils need witnesses or a notary?

Most states require witnesses for codicils, similar to wills. A notary may be used for a self-proving affidavit, which can make probate easier in some states, but the baseline requirements depend on local law. The safest approach is to follow your state's formalities exactly.

Can a codicil change my executor or beneficiaries?

Yes. A codicil can change who serves as executor or successor executor and can add, remove, or alter bequests to beneficiaries. The codicil should reference the original will by date and clearly state what is being changed.

Where should I keep a codicil, and who should get copies?

Store the original codicil with the original will in a safe, accessible location. Tell your named personal representative where the originals are kept. Providing copies to trusted individuals can be helpful, but preserving the originals is critical for probate.

How do codicils impact the probate process and filings?

The will and any codicils are read together as one plan. All originals typically must be filed with the court. Codicils can change beneficiaries, executors, and distributions, which affects notices, inventory, creditor payments, and final distributions. If a codicil's validity is questioned, the court may require additional proof.

Ready to Update Your Will the Right Way?

If you are weighing a codicil versus drafting a new will, we can help you choose a path that supports your goals and complies with your state's requirements. To discuss hiring counsel for targeted updates or a comprehensive refresh, use our contact form or call 414-253-8500 to schedule a consultation and speak with our firm about representation.

Disclaimer: This page provides general information about codicils and wills. It is not legal advice and does not create an attorney-client relationship. Laws vary by state and your circumstances. Consult a licensed attorney about your specific situation.

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