Call rates from College telephones may change as we seek the best provider for the College.

Free calls

The type of calls that are free of charge are:

  • internal calls;
  • calls from College telephones to Mobex (Mobex is the five digit mobile extension associated with the full mobile number of a College mobile);
  • local calls;
  • national calls.

All other calls are chargeable calls. You can also make chargeable calls using a Roaming PIN.


To find out the cost of chargeable calls for St. Mary's Campus or NHS Trust telephones, contact ThamesNet:

Roaming PINs

A roaming PIN is a unique six digit PIN that is allocated to a specific extension. This code allows you to make chargeable calls using any College telephone. Any calls you make using your PIN will be charged back to the billing extension.

Use a roaming PIN

You must wait for the system to prompt you to complete each step below. If you do not wait for the system to prompt you, your call will be unsuccessful.

To use your roaming PIN, follow these steps:

  1. Lift the receiver of the telephone.
  2. Press *72*.
  3. Enter your personal six digit roaming PIN.
  4. Press #.
  5. Press 9 for an external line.
  6. Dial the full telephone number of the person you wish to contact, followed by #.
  7. Replace the receiver to disconnect the call.

Request a roaming PIN

To request a roaming PIN, contact your Telecoms Representative.