How to prove a deceased family member was the sole member of an Idaho LLC — what to get from the Secretary of State

Short answer: The Idaho Secretary of State can provide certified formation documents (Articles/Certificate of Organization) and a Certificate of Existence (good standing). Those records prove the LLC’s formation and current public record items (registered agent, organizers, filings), but they usually do not list private members. To show a bank that your family member was the sole member you will usually combine certified SOS documents with the LLC’s internal documents (operating agreement), the decedent’s death certificate, and probate or estate paperwork that gives you authority to act for the estate.

Disclaimer: This is educational information, not legal advice. Consult an attorney or the bank for guidance specific to your situation.

Detailed answer — what the Secretary of State can and cannot provide

Under Idaho law, the Secretary of State maintains public records about business entities formed in Idaho. From the SOS you can typically obtain:

Certified copy of the Articles (Certificate of Organization) or any filed Articles of Amendment: These show the entity name, formation date, and any filed public amendments. They confirm the LLC exists and the date it was formed.
Certificate of Existence / Certificate of Good Standing: An official SOS certificate that the LLC is or was an active entity on a given date.
Filed statements and annual reports: If the LLC filed an annual report or a public statement (for example a Statement of Authority or an amendment that identifies a manager), those filed records appear in the SOS dossier.
Recorded registered agent information and filing history: The SOS record shows the registered agent and the list of filings you can order (with certified copies).

Important limitation: Idaho’s public formation records usually do not list all members or owners of an LLC. Membership interests and ownership percentages are typically internal matters handled in the LLC’s operating agreement or other internal records. The SOS will not normally certify who the sole member was unless that person’s name appears in a filed public document (for example, a filed amendment or a Statement of Authority that expressly names them).

For official Idaho statutes and the general rules governing business entities, see Idaho Code Title 30 (Corporations, Partnerships and Associations): https://legislature.idaho.gov/statutesrules/idstat/Title30/.

What banks commonly accept to confirm sole membership after a death

Banks often require a combination of public and internal documents plus estate authority documents. Typically they will accept some or all of the following:

Certified Articles/Certificate of Organization from the Idaho Secretary of State to prove the LLC was properly formed.
Certificate of Existence / Good Standing from the Idaho SOS showing the LLC’s active status at or before the member’s death.
Certified copy of any filed amendment or Statement of Authority that explicitly identifies members or managers (if one was filed).
Operating Agreement (certified or a notarized copy) showing the decedent as the sole member. Operating agreements are normally internal documents not filed with the SOS—banks often want a copy signed by the decedent or a notarized copy from the estate or personal representative.
Federal EIN documentation (IRS EIN letter) in the LLC’s name and proof the decedent controlled the account.
Death certificate proving the member’s death.
Probate documents or letters testamentary/letters of administration showing who is authorized to act for the estate and to transfer or access the decedent’s assets, including the decedent’s LLC interest.

If the LLC interest passed by will or intestacy, banks usually require the personal representative’s letters from the probate court. If the estate is small and qualifies for a small-estate affidavit procedure under Idaho law, the bank may accept that instead of full probate—confirm with the bank and consider getting legal advice.

How to get these records from the Idaho Secretary of State

Search the business record on the Idaho SOS business search to locate the LLC’s SOS file number and list of filings: https://sosbiz.idaho.gov/search/business.
Request certified copies of the Articles/Certificate of Organization and any filed amendments or statements. You can also request a Certificate of Existence (Good Standing) from the SOS.
Download or order copies of the filing history so you can see whether any document filed publicly names the member or manager.
If the name of the member does not appear in SOS filings, gather internal LLC documents (operating agreement) and estate authority documents to present to the bank.

Idaho SOS business filing information: https://sos.idaho.gov/business-entities/.

Practical next steps (recommended)

Contact the bank in advance and ask exactly which documents they require to release account access or transfer funds relating to the LLC.
Order certified SOS documents (Articles and Certificate of Existence) and print the LLC’s SOS filing history.
Locate the original Operating Agreement or other internal corporate records showing member ownership. If you can’t find them, ask other family members or the decedent’s attorney for copies.
If you are the personal representative or executor, bring your certified Letters Testamentary or Letters of Administration plus a certified death certificate to the bank.
If the estate is being probated, bring the probate case number and a copy of the court order appointing you as representative.
If you lack authority or if the bank is not satisfied, consult an Idaho probate/estate attorney for next steps to secure the LLC interest for the estate.

Helpful Hints

Ask the bank for a written list of required documents so you avoid multiple trips.
Certified SOS documents are stronger evidence than uncertified prints from the website—order certified copies if the bank requests them.
Operating agreements are usually internal; do not assume the SOS will have them. If the LLC did not have a written operating agreement, other evidence (tax returns, bank signatures, membership certificates) can help show sole ownership.
If the LLC was manager-managed and the manager’s name appears on SOS filings, that public document may make it easier to access accounts—but it does not replace probate authority if the decedent owned the membership interest.
Keep originals and certified copies in a safe place and make several certified copies for banks and professionals.

For Idaho statute guidance on business entities and filings, see Idaho Code Title 30: https://legislature.idaho.gov/statutesrules/idstat/Title30/. For business-record searches and ordering certified documents, see the Idaho Secretary of State business pages: https://sos.idaho.gov/business-entities/ and the business search tool: https://sosbiz.idaho.gov/search/business.

If you want, tell me whether you already have the LLC name, SOS file number, the Operating Agreement, or probate documents and I can outline the exact documents to request and the order to present them to the bank.