We are usually asked about how to get form 6166. Our website: usapostille.com provides it.

We provide a certification service for US Tax Residency Certificate issued by the IRS, which is used in countries participating in the Hague Convention, because we receive an apostille of US tax residency certificate from the US Department of State in Washington DC. And we help businesses authenticate the certificate from the US Department of State and the embassy of the destination country in Washington DC.

If your documents will be used in countries not participating in The Hague, legalization of the embassy is necessary to recognize them. You can order it from our site too.