He was the son of William and Kate MacGrath. In 1901 the family lived in house 5, Montpelier Parade, Blackrock, Dublin. William is recorded as being etired from the Bank.
By 1911 MacGrath was boarding in house 13, Sandy Street, Newry, Co. Down. He is described as a Bank Official.
The London Gazette of 25th April 1919 records
The Belfast Banking Company 'Roll of Honour' booklet records MacGrath as having been awarded military honours, the Military Cross (MC). His last known address is recorded as 'in France'.