Format
Nine digits, formatted XXX-XX-XXXX. Issued by the SSA, not the IRS.
Who has one
- US citizens
- Lawful permanent residents (green-card holders)
- Non-immigrants authorised to work in the US (e.g. holders of certain visas)
A non-US founder who has never worked in the US will not have one. You do not need an SSN to form a US LLC or to be the responsible party on an SS-4.
When it comes up for non-US founders
Rarely, but these scenarios do occur:
- You spent time in the US on a work visa and were issued one; it stays valid for life.
- You later become a green-card holder; you’ll apply for one as part of that process.
- The SSN substitute for non-US filers is an ITIN, which the IRS issues on request.