[Blog]Signature Certificates for Foreign Residents Buying a Car in Japan: When They Replace Seal Certificates and How U.S. Citizens Can Obtain One

2026-02-07

When purchasing and registering a car in Japan, you may be told that an official seal certificate is required. However, depending on your residency status, the type of registration procedure (new registration, transfer, cancellation, etc.), the vehicle type (standard or light vehicle), and the practices of the dealer or registration agent, a “signature certificate” may be accepted instead of a seal certificate. This document confirms that the signature on a form truly belongs to the person signing it. For U.S. citizens, the most practical way to obtain such a document in Japan is through the notarial services provided by the U.S. Embassy or Consulates. For official guidance, see the U.S. Embassy Notarial Services page.

What Is a Signature Certificate and Why Is It Needed?

In Japanese vehicle registration procedures, documents such as powers of attorney or transfer certificates typically require a registered seal and a seal certificate to verify the owner’s identity and intent. However, some foreign residents cannot obtain a seal certificate or are not accustomed to the seal system. In such cases, certain registration processes allow a signature certificate instead. This document confirms that the signature was made by the person concerned and serves as an alternative method of identity verification.

Important Note: It Is Not Always Required

A signature certificate is not automatically required for all foreign residents. If you are registered as a resident in Japan and have completed seal registration at your local municipality, you may simply use the standard combination of a registered seal and a seal certificate. A signature certificate usually becomes relevant only when the registration agent or the transport office accepts it as a substitute. Therefore, the fastest approach is to confirm with the dealer or registration agent exactly which documents and forms of certification are required for your specific transaction.

For U.S. Citizens: Use U.S. Embassy or Consulate Notarial Services

U.S. citizens in Japan can obtain a signature certificate–type document through notarial services at a U.S. Embassy or Consulate. These services are commonly used for car purchases, property transactions, and other legal documents. Details are available on the official notarial services page.

Step-by-Step Process to Obtain a Signature Certificate

1) Confirm what needs to be notarized: Typically, you will need notarization for documents such as a power of attorney or transfer certificate. The notary confirms that the signature was made by you in their presence.

2) Make an appointment: Notarial services at the U.S. Embassy and Consulates are generally by appointment only. Follow the instructions on the official website.

3) Bring the required items: (a) a valid photo ID, usually your passport; (b) the document to be notarized (do not sign it in advance); and (c) the required fee.

4) Understand the fee structure: The U.S. Embassy and Consulates generally charge USD 50 per notarial seal. If multiple signatures or documents require separate notarization, the fee may increase accordingly. See the official fee schedule for details.

Common Practical Tips for Car Transactions

• Bring unsigned documents: If you sign them in advance, the notary may not be able to certify them, and you may have to repeat the process.

• Confirm the required format in advance: Some dealers or registration agents may require specific wording or document styles. Ask if they have a template that has been accepted before.

• Allow enough time: Because the process requires an appointment and security checks, plan your schedule carefully—especially if it affects your parking certificate or delivery date.

Summary: A Practical Checklist to Avoid Delays

(1) Confirm with the dealer or registration agent whether a seal certificate is required and whether a signature certificate is acceptable. (2) If a substitute is needed, determine which documents must be notarized. (3) U.S. citizens should book a notarial appointment at the U.S. Embassy or Consulate and bring unsigned documents and identification. (4) Estimate costs based on the “USD 50 per notarial seal” standard. Following this order can help prevent delays in parking certification and vehicle delivery. Always check the latest information on the Notarial Services page and the Fee Schedule.