I don’t remember my Thailand Social Security number — can I still claim the pension?

日本語版: タイの年金、社会保険番号がわからなくても申請できる？

“I worked in Thailand for years, but my SSO number is long gone — is there any way to claim?”

This is the single most common reason people abandon their claim before even trying. The good news is: the number is recoverable from the SSO’s records, as long as you have a few basic pieces of evidence. You don’t need to remember the number itself to file.

Below I walk through the situations people typically find themselves in, the documents that help, and the lookup service I offer for cases where you can’t visit the SSO in person.

Why the SSO number matters

A Thai Social Security number is the 13-digit identifier (typically starting with “6” for foreign nationals) that the SSO uses to retrieve your contribution history. Every claim is filed by SSO number — without it, there is no record to retrieve and nothing to pay.

The number was assigned to you when your Thai employer first registered you with the SSO. You can find it on:

• Old Thai payslips (usually printed near the deductions section)
• The blue plastic SSO card, if you ever received one
• Records held by your former Thai HR department

If none of those are available, the SSO itself still holds your record — and that record can be looked up.

Five typical situations: which one are you in?

People with missing SSO numbers fall into one of five buckets. Identifying yours tells you how much work the lookup is.

Case A: You have all your SSO numbers, for all your former Thai employers

You’re set. Proceed directly to filing — either on your own or via the application service described in the footer.

Case B: One employer, but you can’t find the number

Start with a quick paper search:

• Old payslips
• The blue SSO card
• Old HR records or letters from the company

If nothing turns up, the lookup at the SSO with your old passport copy and the company’s name is straightforward. See the lookup service section below.

Case C: Multiple employers, all numbers in hand

You can combine all the periods into one claim. Note that in Thailand, each Thai employer often registers you with a new SSO number — so it’s not unusual to have several numbers. As long as you have all of them, the application combines the periods. See I worked at several companies for the procedure.

Case D: Multiple employers, some numbers known and some missing

File for the known periods, and look up the missing ones with the SSO. Total contribution months are calculated by adding all employers together, so the missing periods do count once recovered.

Case E: Multiple employers, no numbers at all

This is the most paperwork-heavy bucket but is still doable. With your old passport copy and the names of your former employers (in Thai or English), each company’s record can be looked up separately and combined.

Common misconception #1: “My number should have followed me from job to job”

In principle, Thailand’s SSO assigns one number per person; in practice, expat workers often end up with separate numbers per employer (see I worked at several companies for why). If your hands hold only one number but you worked at more than one Thai employer, it’s worth checking whether a second one exists before you assume the search is complete.

Common misconception #2: “Records check failed — must mean I have no record”

Sometimes a search returns “no records found.” Before assuming this is final, two angles are worth checking:

The passport number mismatch. The SSO matches applicants by SSO number + passport number. If your current passport has a different number from the one you held while working in Thailand (e.g., because you renewed in the interim), the SSO’s system may treat the searches as different people.

The fix is to provide a copy of your old passport’s photo page. The SSO staff can then link the old passport-era record to your current passport, and the “no records found” result usually reverses.

Company name change or acquisition. If your former Thai employer has been acquired or rebranded since you worked there, SSO records may have been updated under the new company name. A search under the original name comes up empty; a search under the new name returns the record.

One real example I worked with: a search for “Sanyo Universal Electric” came up empty, but the same record was on file under the post-acquisition name “Haier Thailand.” Asking the staff to check both names produced the result.

If you’re unsure what the post-acquisition or current name of your old employer is, an English-language search (“what is OLD_NAME Thailand now called?”) usually surfaces it quickly.

The lookup service: how it works

For overseas applicants — and for anyone in Thailand who would rather not spend a half-day at an SSO branch — I offer a dedicated SSO number lookup service.

What you provide:

• A copy of your old passport’s photo page (from when you worked in Thailand)
• The name of your former Thai employer, ideally in both English and Thai. A Thai-language business card, an employee ID, or even just the company’s Tax ID (TIN) is enough — from the Tax ID, the company’s official Thai-language registered name can be looked up
• Approximate years and months of employment (year-month precision is fine)

What I do:

• Visit the SSO office with your documents
• Look up your record by combining (a) old passport, (b) former employer, (c) approximate dates
• Confirm the SSO number(s), total contribution months, and estimated benefit amount
• Report back to you, in English, by email

What you receive:

• Your SSO number(s) — one per Thai employer, in some cases more than one
• Total contribution months across all employers
• Estimated benefit amount (lump sum or lifetime pension)
• A clear picture of whether the full application is worth pursuing

Fee: USD 60 (THB 2,000 / JPY 10,000), depending on which currency is convenient for you.

This fee covers the research time at the SSO. It is paid in advance and is not refundable, even if no records are found. (The full-application service has a separate refund policy — see the service fee section below.)

After the lookup: decide whether to proceed

Once you have the number(s) and the estimated benefit amount in hand, you can decide whether the full application is worth the further fee. For most applicants the answer is yes — the benefit is typically several times the application fee — but seeing the actual numbers makes it an informed decision rather than a leap of faith.

If you do proceed, the lookup fee is separate from the application fee and is not credited toward it. (They cover different work.)

Read next

• The complete guide to Thailand’s old-age benefit
• How much will I actually receive?
• I worked at several companies — can I combine the periods?
• Can I claim if I no longer live in Thailand?

Just want to start with a lookup?

If you’d like to start with just the SSO number lookup before committing to the full application:

• Fee: USD 60 / JPY 10,000 / THB 2,000 (see above — non-refundable)
• What you provide: old passport photo page + former employer name(s) + approximate dates
• What you receive: SSO number(s), contribution months, estimated benefit amount

If you’d prefer to skip straight to the full application, see the service fee table below.

Service fee (full application)

The fee depends on the bank account you want to receive the benefit into:

This is a flat fee. There is no success fee and no additional charges. If it turns out that you are not eligible, I refund the full amount.

About the author

I’m Takehiko Nishizawa, originally from Saitama, Japan. I have been working for a Japanese company in Thailand for 25 years. During that time I have helped more than 40 former expat workers claim their social security old-age benefit from the Thai SSO. Every applicant who knew their Social Security number has successfully received their benefit. There have been no failed cases.

Get in touch

For questions or to start your application — or just the lookup — please contact me through this form. I usually reply within 24 hours. You can also find me on X at @nisizawa.

This article provides general information about Thailand’s social security old-age benefit and is based on the author’s hands-on experience helping former expat workers file their claims. It does not constitute legal, tax, or financial advice. Tax treatment of the benefit varies by your country of residence — please consult a local tax or legal advisor for your specific situation. Procedures and amounts at the Social Security Office may change without notice; the description here reflects practice as of 2026.