Home2016 Treaties and Agreements ...Czech Republic (16-501) – Supplementary Agreement Amending the Agreement of September 7, 2007 on Social Security hide Czech Republic (16-501) – Supplementary Agreement Amending the Agreement of September 7, 2007 on Social Security TIAS Office of Treaty Affairs May 1, 2016 Social Security Signed at Prague September 23, 2013; entered into force May 1, 2016. Amendment of agreement done September 7, 2007: TIAS 09-101.2 Download attachment [256 KB] Tags Czech Republic Social Security Treaties