| No. | Date | Cover | Title |
|---|---|---|---|
| 1 | 21 Mar 1990 | |
Art Series - Lithographs of 19th Century Singapore |
| 2 | 3 May 1990 | |
150 Years of Postage Stamps |
| 3 | 4 Jul 1990 | |
Definitive Postage Stamps - Tourism Series (Low Values) |
| 4 | 16 Aug 1990 | |
25 Years of Independence |
| 5 | 9 Oct 1990 | |
Definitive Postage Stamps - Tourism Series (High Values) |
| 6 | 14 Nov 1990 | |
Ferns of Singapore |