The former Doctor Who actor's voice has been responsible for reading out text messages sent to landline numbers since January 2006.
BT stated that the service was being changed to give users a choice between male and female voices.
From 1 May all texts will be read out in a female voice unless users insert *M# in front of the text message to choose a male voice.
"Our research shows that people need to think carefully when choosing a male or female voice to deliver their texts," said a BT statement.
"Seven out of 10 people think that male voices are better for telling jokes. Male voices were considered more powerful and better for disciplining children, while female voices were described as more comforting, truthful and persuasive. "
BT said that Baker's iconic voice had proved popular and that the number of texts sent to landlines rose by 69 per cent in the first week of the promotion. More than 11 million texts sent to landlines have been delivered in Baker's voice.
"Tom Baker has been a huge success and a great way to introduce a new audience to BT Text," said Wendy McMillan, BT's general manager for consumer services.
"As the technology develops we want to give people the option to have their texts delivered to landlines in a gender that is the same as their own or one they think will be more effective depending on the message they're sending."
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