| COUNTRY | FORM | PHOTO | BUSINESS LETTER | ITIN | OTHER REQUIREMENTS | NORMAL | RUSH |
| Saudi Arabia | PDF | 1 | Letter from U.S. Company | Yes | Invitation from the Ministry of Foreign Affairs in Saudi Arabia and a Visiting Visa Request form | 10 | 5 |
| Serbia | No Visa required for stay of up to 90 days. |
| Sierra Leone | 1 | 1 | Letter from U.S. Company | Yes | N/A | Varies |
| Singapore | No Visa required for stay of up to 30 days. Hotel confirmation will be required. |
| Slovak Republic | No Visa required for stay of up to 30 days. |
| Slovenia | No Visa required for stay of up to 90 days. |
| South Africa | No Visa required for stay of up to 90 days. |
| Spain | No Visa required for stay of up to 90 days. |
| Sri Lanka | PDF | 2 | Letter from U.S. Company | Yes | Invitation | 7 | 5 |
| Sudan | 1 | 2 | Letter from U.S. Company | Yes | Invitation and vaccination. | 10 | 7 |
| Sweden | No Visa required for stay of up to 30 days. |
| Switzerland | No Visa required for stay of up to 30 days. |
| Syria | 1 | 2 (signed) | Letter from U.S. Company | Yes | N/A | 14 | 10 |