 Holt was Member of Parliament (MP) for Preston North from 1970 to 1974, when she lost the seat in the February election of that year to Labour's Ronald Atkins (from whom she had won the seat in 1970).She was the first woman to hold the Preston North seat.In Parliament, she was a strong advocate for the Domicile and Matrimonial Proceedings Act 1973, which allowed wives have different addresses than their husbands.