Free, MyHeritage has added index records of 571,917 crew members of the United Kingdom Merchant Navy. Records typically include the name of the seaman, date and place of birth, and the service number. The forename(s) is often just the initials.
While there are scattered entries for births from the 1820s the major part is for births from the 1870s to the 1960s.
The records in this collection were sourced from The National Archives which has an extensive merchant navy collection found by searching TNA’s research guides.