| Record Number | Keyword(s) | Country | Catalog Listed? | Continent | |
| 2921 | Y.C.C.P. | Ukraine. | Real | Europe |  |
| 2922 | Y.C.P.P. | Ukraine, semipostals (1923). | Real | Europe |  |
| 2923 | YAR | Yemen Arab Republic (1963-present). | Real | Asia |  |
| 2924 | YCA (overprint) | Peru- Yca- Chilean occupation (1884). | Real | Americas |  |
| 2925 | YCA VAPOR (overprint) | Peru- Yea- Chilean occupation (1884). | Real | Americas |  |
| 2926 | YCTAB | Montenegro (1905). | Real | Europe |  |
| 2927 | YEMEN PDR | Yemen People’s Democratic Republic. | Real | Asia |  |
| 2928 | YEN (currency) | Japan, Manchukuo, Ryukyu Islands. | Real | Asia |  |
| 2929 | YKP. H. PEП (overprint on stamps of Austria) | Western Ukraine. | Real | Europe |  |
| 2930 | YKP. H.P. (overprint on stamps of Austria) | Western Ukraine. | Real | Europe |  |
| 2931 | YKPAIHCbKA P.O.П.Й.T. | Ukraine. | Real | Europe |  |
| 2932 | YKSI MARKKA | Finland (1866-74). | Real | Europe |  |
| 2933 | YN. (currency) | Japan, Manchukuo, Ryukyu Islands. | Real | Asia | |
| 2934 | YUNNAN FOU (overprint on stamps of Indo-China) | France- Offices in China- Yunnan Fou (1906-19). | Real | Asia |  |
| 2935 | YUNNAN SEN (overprint on stamps of Indo-China) | France- Offices in China- Yunnan Fou (1903-5). | Real | Asia |  |
| 3134 | Yemen (Mutawakelite Kingdom) | Yemen (Mutawakelite Kingdom) (stamp issuing country) 1926 - 1970 | Real | Asia |  |
| 3135 | Yemen Arab Republic | Yemen Arab Republic (stamp issuing country) 1963 - 1990 | Real | Asia |  |
| 3136 | Yemen PDR | Yemen PDR (stamp issuing country) 1971 - 1990 | Real | Asia |  |
| 3137 | Yemen Republic | Yemen Republic (stamp issuing country) 1990 | Real | Asia |  |
| 3138 | Yucatán | Yucatán (stamp issuing country) 1924 only | Real | Americas |  |
| 3139 | Yugoslav Government in Exile | Yugoslav Government in Exile (stamp issuing country) 1943 - 1945 | Real | Europe |  |
| 3141 | Yugoslavia (Democratic Federation) | Yugoslavia (Democratic Federation) (stamp issuing country) 1944 - 1945 | Real | Europe |  |
| 3142 | Yugoslavia (Kingdom) | Yugoslavia (Kingdom) (stamp issuing country) 1929 - 1941 | Real | Europe |  |
| 3143 | Yunnan | Yunnan (stamp issuing country) 1926 - 1933 | Real | Asia |  |
| 3144 | Yunnanfu (IndoChinese Post Office) | Yunnanfu (IndoChinese Post Office) (stamp issuing country) 1903 - 1922 | Real | Asia |  |