How to Get a Signature Guarantee: Where to Go, Costs, and Requirements

To get a Medallion signature guarantee, visit a bank, credit union, or broker-dealer that participates in one of the three recognized Medallion programs, bring a government-issued photo ID, proof that you own the securities, and the unsigned transfer form, and sign the form in person in front of an authorized officer who will apply the Medallion stamp. Most institutions provide the service only to existing customers, and the stamp itself must carry a coverage limit high enough for the value of the transfer.

Where to Go

Federal regulations limit who can issue the guarantee to five categories of institutions: banks, savings associations, credit unions, broker-dealers, and national securities exchanges, clearing agencies, and registered securities associations.¹ The institution must also belong to one of three programs: the Securities Transfer Agents Medallion Program (STAMP), the Stock Exchanges Medallion Program (SEMP), or the New York Stock Exchange Medallion Signature Program (MSP).² STAMP is the largest, with more than 7,000 participating institutions in the U.S. and Canada.

Being able to walk into an eligible institution is not the same as being able to get a stamp there. Because the guarantor takes on financial liability if the signature turns out to be forged, most banks and credit unions provide the service only to existing customers whose accounts have been open for a minimum period, often six months.³ Call ahead. Confirm that an authorized officer will be at the branch during the hours you plan to visit, since not every location has one on staff.

One thing to rule out early: a notary public cannot substitute for a Medallion guarantor on a securities transfer. Notarization verifies your identity and witnesses your signature but carries no financial guarantee, and transfer agents will reject a document that has a notary seal in place of a Medallion stamp.⁴

What to Bring

Arriving prepared prevents a wasted trip. At a minimum, you need three things:

A valid government-issued photo ID such as a driver’s license, state ID, or current U.S. passport. The name on the ID must match the name on the securities account exactly.
Proof of ownership: the original stock certificate or a recent account statement from your brokerage, generally dated within the past year.³
The transfer form from the security’s transfer agent, filled out completely but not signed. You sign it in front of the officer.⁴

Some transfers need more paperwork. If the account holder has died, expect to bring a certified copy of the death certificate and, depending on the registration, court-issued letters testamentary showing your authority as executor.⁵ Securities held in a trust generally require a trustee certification form and photo IDs for all trustees.³ For a corporation, partnership, or other entity, plan on formation documents, a corporate resolution authorizing the transfer, or a certificate of incumbency establishing your authority.

The In-Person Signing

The signing happens in front of the officer, without exception. A form you signed before the appointment is invalid and cannot be guaranteed. The officer verifies your identity and ownership documents, watches you sign, and applies the Medallion stamp, which carries a unique identification number tying the guarantee back to that specific institution and officer.

Once stamped, the document becomes high-value paper. Send it to the transfer agent by certified mail or a private courier with tracking. Losing a stamped original causes serious delays, and each transfer agent sets its own window for how long after stamping it will still accept the document, so ask the agent how much time you have before the stamp goes stale. If there is a delay, you may need to return to the guarantor for a fresh stamp.

Match the Stamp to the Transfer Value

Every Medallion stamp carries a single-letter prefix that caps the dollar value it can guarantee in one transaction. If the market value of the securities exceeds that cap, the transfer agent rejects the document. Before your appointment, check the current value of what you are transferring and confirm the institution’s stamp covers it. The prefixes and their limits are:⁶

Z: $10,000,000 (or $14,000,000 for Security Transfer Association members)
Y: $5,000,000
X: $2,000,000
A: $1,000,000
B: $750,000
C: $500,000
D: $250,000
E: $100,000
F: $100,000 (most credit unions)

A small credit union with an F-prefix stamp cannot guarantee a $150,000 transfer. If your usual institution’s cap is too low, you will need to find a bank or broker-dealer with a higher-tier stamp.

What It Costs

Many banks, credit unions, and brokerage firms provide the guarantee free of charge to existing customers who meet their relationship requirements.³ For non-customers, institutions that will still perform the service typically charge $10 to $50, and more complex situations or third-party services can run $100 or more. Confirm the fee, and whether the institution serves non-customers at all, before you go.

If You Don’t Have a Qualifying Account

The customer-relationship requirement is the most common obstacle. A few workarounds:

Ask your brokerage or financial advisor. Even a firm without physical branches can sometimes arrange a guarantee through its clearing firm or a partner institution.
Open an account and wait out the eligibility period. Some institutions provide the service after you deposit funds, though many still impose a waiting period.
Try local credit unions. Policies for new members are sometimes more flexible than those at large national banks.
Use an online service. The Securities Transfer Association lists eSignatureGuarantee.com, where you verify your identity through a secure platform, submit supporting documents, and receive a stamped document by courier. Third-party services generally cost more than banks.⁷

Shareholders holding U.S. securities from abroad can also find STAMP-participating firms in the United Kingdom and Australia through the Securities Transfer Association.⁷

1
eCFR. 17 CFR 240.17Ad-15 – Signature Guarantees
2
U.S. Securities and Exchange Commission. Medallion Signature Guarantees: Preventing the Unauthorized Transfer of Securities
3
Bank of America. Medallion Signature Guarantee
4
TreasuryDirect. Signature Certification
5
Investor.gov. Transferring Assets
6
Computershare. What Is a Medallion Guarantee
7
Securities Transfer Association. Medallion Guarantee