DIY Estate Planning Montana: Common Mistakes and How to Avoid Them

Montana is one of the more DIY-friendly states for estate planning. The Uniform Probate Code simplifies the probate process, the state has no estate or inheritance tax, and several powerful probate-avoidance tools are available for free or minimal cost. For straightforward estates, you don't need to pay an attorney $2,000-$5,000 to create a functional plan.

But "DIY-friendly" doesn't mean "mistake-proof." The most common errors don't come from doing estate planning without a lawyer — they come from incomplete planning that creates gaps between your documents, your account structures, and Montana law.

Mistake 1: Writing a Will But Ignoring Beneficiary Designations

This is the most expensive mistake in DIY estate planning, and it happens constantly. You spend time crafting a will that divides everything equally among your three children. Meanwhile, your 401(k) still names your ex-spouse from 15 years ago, your life insurance policy has no beneficiary listed, and your bank accounts have no POD designations.

The will controls none of those assets. Beneficiary designations on retirement accounts, life insurance policies, and POD/TOD financial accounts override your will completely. If there's a conflict, the beneficiary designation wins every time.

Fix: After writing your will, audit every account that allows a beneficiary designation. Make sure they all align with what your will says. Then check them annually — beneficiary designations don't update themselves when your life circumstances change.

Mistake 2: Skipping the Self-Proving Affidavit

Montana allows you to attach a self-proving affidavit to your will under MCA 72-2-524. This notarized statement from you and your witnesses lets the probate court accept your will without having to locate and produce your witnesses after your death.

Most DIY estate planners skip this step because it requires a notary appointment. The cost of that decision: your personal representative may spend weeks or months tracking down witnesses who have moved, changed names, or become unreachable. If witnesses can't be found, the court requires additional evidence to admit the will — adding time, expense, and uncertainty.

Fix: When you sign your will, schedule the witness signing at a location with a notary. Banks, UPS stores, and law offices offer notary services for $5-$10 per signature. Twenty minutes now saves your family weeks later.

Mistake 3: Not Recording a TOD Deed on Real Property

Your home is probably your most valuable asset. Without a Transfer on Death deed or joint tenancy with right of survivorship, your home goes through probate — even if everything else in your estate is covered by beneficiary designations and the small estate affidavit.

Montana's TOD deed under MCA 72-6-408 is one of the most powerful free tools available. You fill out the deed, get it notarized, and record it at the County Clerk and Recorder for about $20. The deed is revocable during your lifetime and transfers your home directly to your named beneficiary at death.

Fix: Record a TOD deed on every piece of real property you own. Each deed must include the property's full legal description (available from your deed or the county assessor) — street addresses are not legally sufficient.

Mistake 4: Leaving Your Plan as Separate, Uncoordinated Documents

A will says one thing. Your TOD deed names a different beneficiary. Your bank POD designation names a third person. None of these documents reference each other, and nobody knows what the complete plan looks like.

This "document soup" approach is common when DIY planners address one asset at a time over months or years, without ever stepping back to see the full picture. Contradictions between documents don't cause legal invalidity — they cause family conflict, because each beneficiary has a legitimate claim under a different instrument.

Fix: Create a master inventory that lists every asset, how it's titled, who the current beneficiary is, and what happens to it at death. Review the whole picture for conflicts before finalizing any individual document.

Mistake 5: Forgetting Powers of Attorney

Estate planning isn't just about death — it's about incapacity. If you suffer a stroke, develop dementia, or are in a serious accident, someone needs legal authority to manage your finances and make medical decisions on your behalf.

Without a durable power of attorney, your family must petition the Montana district court for conservatorship or guardianship — a process that takes months, costs thousands, and puts a judge in charge of choosing who manages your affairs.

Fix: Execute both a financial power of attorney (durable, so it survives your incapacity) and a medical power of attorney or Advance Health Care Directive. Register the medical directive with the Montana Department of Justice End-of-Life Registry so hospitals can access it electronically.

Mistake 6: Relying on Joint Tenancy as Your Entire Plan

Joint tenancy with right of survivorship is simple and effective between spouses — when one dies, the other automatically owns the asset. Many couples stop here.

The problem is the second death. When the surviving spouse dies, every asset that was formerly held jointly is now solely in their name — and goes through probate. Joint tenancy between spouses solves the first death but does nothing for the second.

For blended families, joint tenancy creates an additional risk: the surviving spouse becomes the sole owner and can leave the property to anyone, potentially disinheriting the first spouse's children entirely.

Fix: Use joint tenancy as one tool among many. Combine it with TOD deeds, beneficiary designations, and a will that addresses the second-death scenario.

Mistake 7: Using Out-of-State Templates Without Modification

National legal document services create templates for all 50 states using the same basic structure. These templates often miss Montana-specific provisions: the personal representative powers under MCA 72-3-715, the 120-hour survival requirement under MCA 72-2-114, the self-proving affidavit format under MCA 72-2-524, and the elective share protections under MCA 72-2-221.

A template that was perfectly adequate in California may create ambiguities or gaps when applied in a Montana probate court.

Fix: Use Montana-specific documents that reference the correct statutes and include state-specific provisions. The Montana Basic Estate Planning Kit is designed for exactly this — every document template is built around Montana's Uniform Probate Code and coordinated to work as an integrated plan rather than isolated forms.

When to Hire an Attorney Instead

DIY estate planning works for straightforward situations: modest estates, single or first marriages, adult children, no business interests. Hire an attorney if you have a taxable estate (over $13.61 million), children with special needs, complex business or agricultural succession issues, or expect your plan to be contested.

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