She was educated at the Dominican School in Eccles Street, Dublin, and spent the academic year 1907–1908 studying in Amiens, France on an early exchange programme.
During her time as wife to the Taoiseach she kept a low profile and enjoyed a background role in her husbands' political career.
She was at her husband's side in Canada in 1948, when he announced that the Irish Free State would be leaving the British Commonwealth and declaring itself a republic.
Ida Costello suffered from high blood pressure later in her adult life and in 1956 was diagnosed with chronic bacterial endocarditis, an inflammation of the lining of the heart.
She was admitted to St. Vincent's Private Nursing Home in Leeson Street, but died from heart failure on 20 April 1956, at the age of 64.