Changes to the construction programme as a result of the outbreak of World War One led to the reallocation of many of the 15-inch turrets ordered for the last of the RN 'R' class battleships in 1913-15. There were a further series of reallocations during World War Two to accommodate the Monitor programme and the construction of HMS Vanguard.
The following table has been compiled from a number of secondary sources, some of which conflict, but is believed to be correct based on the information available.
Ship Turrets Ordered For | Ship Initially Fitted To | Ship Subsequently Fitted To |
| Ramillies (4 turrets ordered in July 13) | Marshal Ney | Terror |
| Marshal Soult | Roberts | |
| Glorious (A) | Vanguard (A) | |
| Glorious (Y) | Vanguard (B) | |
| Resolution (4 turrets ordered in July 13) | Resolution (X) | |
| Resolution (Y) | ||
| Repulse (A) | ||
| Repulse (B) | ||
| Repulse (4 turrets ordered in May 14) | Repulse (Y) | |
| Courageous (Y) | Vanguard (X) | |
| Resolution (A) | ||
| Resolution (B) | ||
| Renown (4 turrets ordered in May 14) | Renown | |
| Renown | ||
| Renown | ||
| Courageous (A) | Vanguard (Y) | |
| Replacement Ramillies turrets (4 turrets ordered in 1915) | Ramillies | |
| Ramillies | ||
| Ramillies | ||
| Ramillies | ||
| Two turrets ordered for Furious to be fitted as an alternative to the 18" guns. | Erebus | |
| Abercrombie |
