The fine is payable to Ofcom and passed on to HM Treasury and TalkTalk is required to pay it within 30 days of receiving the penalty notification.
Ofcom consumer group director Claudio Pollack said: "Silent and abandoned calls can cause annoyance and distress to consumers. Companies must abide by the law and Ofcom's policies. If they fail to do so then Ofcom will take firm action.
"Today's penalty sends out a strong message to organisations using call centres that they must comply or face the consequences."
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