| Country | Action | Action Date | Effective Date |
|---|---|---|---|
| Australia | Accession | 04/05/1928 | |
| Canada | Accession | 18/09/1928 | |
| India | Accession | 04/08/1928 | |
| Irish Free State | Accession | 04/05/1928 | |
| LITHUANIA | Signature | 18/05/1926 | |
| LITHUANIA | Ratification | 25/04/1927 | |
| Malay States, Federated | Accession | 18/05/1928 | |
| Malay States, Unfederated | Accession | 01/10/1928 | |
| NAURU | Accession | 11/05/1928 | |
| New Guinea | Accession | 11/05/1928 | |
| New Zealand | Accession | 04/05/1928 | |
| Newfoundland (UK) | Accession | 04/05/1928 | |
| North Borneo | Accession | 18/05/1928 | |
| South Africa | Accession | 04/08/1928 | |
| South West Africa | Accession | 11/05/1928 | |
| UNITED KINGDOM | Signature | 18/05/1926 | |
| UNITED KINGDOM | Ratification | 07/07/1926 | |
| WESTERN SAMOA | Accession | 11/05/1928 |