| Country | Action | Action Date | Effective Date |
|---|---|---|---|
| Australia | Accession | 23/02/1927 | |
| Brunei | Extension | 26/08/1927 | |
| Cameroons | Accession | 10/03/1927 | |
| Canada | Accession | 21/09/1928 | |
| ESTONIA | Signature | 18/11/1925 | |
| ESTONIA | Ratification | 23/04/1926 | |
| India | Accession | 23/02/1927 | |
| Irish Free State | Accession | 23/02/1927 | |
| Malay States, Federated | Accession | 26/08/1927 | |
| Malay States, Unfederated | Extension | 26/08/1927 | |
| Malay States, Unfederated | Extension | 28/09/1934 | |
| New Zealand | Accession | 23/02/1927 | |
| Newfoundland (UK) | Accession | 23/02/1927 | |
| North Borneo | Accession | 10/03/1927 | |
| Palestine | Accession | 10/03/1927 | |
| Papua New Guinea | Accession | 10/03/1927 | |
| South Africa | Accession | 23/02/1927 | |
| South West Africa | Accession | 10/03/1927 | |
| Tanganyika | Accession | 10/03/1927 | |
| Togoland | Accession | 10/03/1927 | |
| UNITED KINGDOM | Signature | 18/11/1925 | |
| UNITED KINGDOM | Ratification | 16/12/1925 | |
| UNITED KINGDOM | Extension | 19/10/1934 | |
| WESTERN SAMOA | Accession | 10/03/1927 |