Please note that people from the following countries are excluded from participating in the IDO (a person can't be a citizen, resident, located, or domiciled in any of these countries)
- American Samoa
- Armenia
- Afghanistan
- Albania
- Angola
- Azerbaijan
- Barbados
- Belarus
- Bosnia and Herzegovina
- Botswana
- Burkina Faso
- Burundi
- Cambodia
- Cameroon
- Central African Republic
- China
- Congo
- Congo (Democratic Republic)
- Cuba
- Chad
- Eritrea
- Ethiopia
- Guam
- Ghana
- Guinea
- Guinea-Bissau
- Haiti
- Hong Kong
- Iran
- Iraq
- Lao People's Democratic Republic
- Lebanon
- Liberia
- Libya
- Madagascar
- Mali
- Mozambique
- Myanmar
- Nicaragua
- Northern Mariana Islands
- North Korea
- Puerto Rico
- Pakistan
- Russia
- Somalia
- South Sudan
- Sudan
- Syria
- Tajikistan
- Trinidad and Tobago
- Turkmenistan
- Taiwan
- Uganda
- Ukraine
- United States
- Uzbekistan
- Vanuatu
- Venezuela
- Virgin Islands (U.S.)
- Yemen
- Zimbabwe