The Office of Telecommunications constantly strives to bring the latest phone and network technologies to the Caltech campus.

For assistance in determining telephone-related services that will best meet your needs, or to request information about your account, please contact us at (626) 395-5995.

Switchboard Hours: Monday through Friday: 7am to 6pm

Campus Operator: Dial 0.

Campus Calls: Dial four-digit extension number.

Emergencies: Dial 5000. Do not use 911. (See inside front cover of the campus directory for instructions.)

Outgoing Calls:

  • Area code 626: Dial 9 + seven-digit phone number.
  • Area codes 213, 310, 323, 562, 818: Dial 9 + 1 + area code + phone number.
  • Calls to a toll-free number: Dial 9 + 1 + toll-free area code + phone number.

    Note: All other outgoing calls require a Caltech authorization code or personal credit card.
    Otherwise, they must be made collect, or billed to a third party.

Calls to JPL Via Tie Line: Dial 777 + five-digit extension.

Calls to Campus from JPL Via Tie Line: Dial 161 + four-digit extension.


Training is available for groups or individuals. Topics include the various types of telephones in use on campus, as well as instructions on using the campus voice mail system. For additional information, contact our office.

Access Authorization Codes

An Access Authorization Code allows on-campus users to make long distance calls and have the calls billed to a departmental account or a student account. For additional information, click here, or call Vicky Lopez at x4742.


Billing Questions

For questions regarding all telephone service-related charges, please call the Telecommunications office (x5995).

Mobile Phones and Smartphones

Mobile phones can be ordered through the Office of Telecommunications. Due to the large number of carriers and phone models, we rely on Corporate Wireless for evaluation, advice, and product delivery. For a list of phone models and descriptions, please refer to the Corporate Wireless web site for price information or to order, call Vicky Lopez at x4742.

Mobile Device Charges

A $50 fee will be charged for each mobile device obtained and paid for through our office. Some of the advantages of using our services include help with the initial selection and configuration of the device, account management services, and access to preferred customer care (more details).

Conference Calls

You can connect up to six parties from your own digital campus telephone.

To have the Campus switchboard connect three to six parties, dial 0 for the campus operator(Monday to Friday, 7am to5pm).

For more than six parties, a conference calling service is available. Please contact Vicky Lopez at ext. 4742 for more details..


Printed campus directories may be ordered through Graphic Resources. For more information please call x6701.

To update your own personal information for the directory listing, log in to Access.Caltech, using your IMSS username and password.

SBC (Pacific Bell) directories may be obtained through this office.
For price information, or to order, call Vicky Lopez at x4742.

Voice Mail

  1. Intuity Audix is Caltech‘s voice messaging system.
  2. Audix is available 24 hours a day.
  3. Monthly voice mail charges are $6.00.
  4. For additional information, call x4742.
  5. For tips on using voice mail, refer to our Web page:
  6. Two quick notes:
    • To retrieve your voice mail when you are not at the office, dial 888-406-3300.
    • To leave a message for a voice mail user without disturbing the user, dial 626-395-5915.