The following charts show what to dial in order to call one UChicago campus phone from another, depending on your location. The first chart shows the dialing instructions when making calls to UChicago sites in the United States, the second chart shows the dialing instructions for calls to UChicago sites in other countries.
The highlighted boxes denotes onsite calls, for example calls placed from a Hyde Park campus phone number to another Hyde Park campus phone number.
| From/To Domestic |
to 170: Chicago Hyde Park Campus |
to 171: Chicago 401 N. Michigan |
to 172: Chicago Gleacher |
to 173: Washington DC |
to 174: San Francisco |
| from: Chicago Hyde Park Campus |
5 digits | 171+5 digits | 172+4 digits | 173+5 digits | 174+5 digits |
| from: Chicago 401 N. Michigan |
170+5 digits | 5 digits | 172+4 digits | 173+5 digits | 174+5 digits |
| from: Chicago Gleacher |
170+5 digits | 171+5 digits | 4 digits | 173+5 digits | 174+5 digits |
| from: Washington DC |
170+5 digits | 171+5 digits | 172+4 digits | 5 digits | 174+5 digits |
| from: San Francisco |
170+5 digits | 171+5 digits | 172+4 digits | 173+5 digits | 5 digits |
| from: London |
170+5 digits | 171+5 digits | 172+4 digits | 173+5 digits | 174+5 digits |
| from: Paris |
170+5 digits | 171+5 digits | 172+4 digits | 173+5 digits | 174+5 digits |
| from: Hong Kong |
170+5 digits | 171+5 digits | 172+4 digits | 173+5 digits | 174+5 digits |
| from: Singapore |
170+5 digits | 171+5 digits | 172+4 digits | 173+5 digits | 174+5 digits |
| from: New Delhi |
170+5 digits | 171+5 digits | 172+4 digits | 173+5 digits | 174+5 digits |
| from: Beijing |
Standard International Dialing | Standard International Dialing | Standard International Dialing | Standard International Dialing | Standard International Dialing |
| From/To International |
to 165: London |
to 166: Paris |
to 176: Hong Kong |
to 164: Singapore |
to 178: New Delhi |
to 163: Beijing |
| from: Chicago Hyde Park Campus |
165+4 digits | PROPOSED-NOT IN SERVICE 166+3 digits | 176+3 digits | 164+4 digits | 178+3 digits | Standard International Dialing |
| from: Chicago 401 N. Michigan |
165+4 digits | PROPOSED-NOT IN SERVICE 166+3 digits | 176+3 digits | 164+4 digits | 178+3 digits | Standard International Dialing |
| from: Chicago Gleacher |
165+4 digits | PROPOSED-NOT IN SERVICE 166+3 digits | 176+3 digits | 164+4 digits | 178+3 digits | Standard International Dialing |
| from: Washington DC |
165+4 digits | PROPOSED-NOT IN SERVICE 166+3 digits | 176+3 digits | 164+4 digits | 178+3 digits | Standard International Dialing |
| from: San Francisco |
165+4 digits | PROPOSED-NOT IN SERVICE | 166+3 digits | 176+3 digits | 164+4 digits | Standard International Dialing |
| from: London |
5 digits | PROPOSED-NOT IN SERVICE 166+3 digits | 176+3 digits | 164+4 digits | 178+3 digits | Standard International Dialing |
| from: Paris |
165+4 digits | 3 digits | 176+3 digits | 164+4 digits | 178+3 digits | Standard International Dialing |
| from: Hong Kong |
165+4 digits | PROPOSED-NOT IN SERVICE 166+3 digits | 3 digits | 164+4 digits | 178+3 digits | Standard International Dialing |
| from: Singapore |
165+4 digits | PROPOSED-NOT IN SERVICE 166+3 digits | 176+3 digits | 4 digits | 178+3 digits | Standard International Dialing |
| from: New Delhi |
165+4 digits | PROPOSED-NOT IN SERVICE 166+3 digits | 176+3 digits | 164+4 digits | 3 digits | Standard International Dialing |
| from: Beijing |
Standard International Dialing | Standard International Dialing | Standard International Dialing | Standard International Dialing | Standard International Dialing | local pattern |
For example, London is assigned "site code 165." This means that all other UChicago sites will dial "165 plus the last 4 digits of the desk phones" in London to reach a London party. Conversely, calling from London to Chicago Hyde Park, one should call "170 + xxxxx", where "xxxxx" are the last five digits of the campus numbers in Hyde Park. Please note that not all sites use five-digit extensions, such as Gleacher, which uses four.