TTM03590 | Qualifying companies and ships: When does a ship cease to be qualifying?
From HM Revenue & Customs · Tonnage Tax Manual
Ship ceases to qualify
A ship will cease to be qualifying when it:
Ship does not cease to qualify
A qualifying ship remains qualifying through most stages of its working life. Thus, it continues to be used for a qualifying purpose when:
in ballast,
laid up awaiting a charter,
in dry-dock undergoing a refit, or
being repaired.
A ship that is laid up for a long period because of industry conditions or world markets will remain a qualifying ship and the tonnage tax regime will continue to apply to it provided:
it remains certified for navigation at sea;
the training commitment is maintained; and
it does not otherwise become a non-qualifying ship.