ðə fˈɜːst θɹˈiː dˈɪdʒɪts əvə səbskɹˈaɪbɚ nˈʌmbɚ kəntˈɪnjuːd tʊ ˈɪndᵻkˌeɪt ðɪ ɛkstʃˈeɪndʒ tʊ wˌɪtʃ ðə nˈʌmbɚ bᵻlˈɔŋd; fɔːɹ ɛɡzˈæmpəl, "tˈuːhˈʌndɹɪd twˈɛnti tˈuː wˈʌn θˈaʊzənd tˈuːhˈʌndɹɪd θˈɜːɾi fˈoːɹ" wʌz ɪn wˈɛstmɪnstɚ sˈɛntɹəl sˈɛktɚ ænd "nˈaɪnhˈʌndɹɪd fˈoːɹɾi sˈɪks wˈʌn θˈaʊzənd tˈuːhˈʌndɹɪd θˈɜːɾi fˈoːɹ" ɪn wˈɪmbəldən sˈaʊθ wˈɛst sˈɛktɚ.
The first three digits of a subscriber number continued to indicate the exchange to which the number belonged; for example, "222 1234" was in Westminster (Central Sector) and "946 1234" in Wimbledon (South West Sector).