Unfortunately, he doesn't fit the definition I currently use, though Wilf is still a great character.
I classify companions as characters that have had multiple consecutive adventures with the Doctor in more than one story. This includes people like Katarina and Adam, but exludes those like Wilf and Kazran.
Kazran Sardick has had multiple consecutive adventures with the Doctor, but they all happened during "A Christmas Carol." This is similar to Sara Kingdom who only has "The Daleks' Master Plan" on TV; however, Big Finish have multiple stories set during that story which heavily expand her role as a companion. "The Churchill Years" boxset coming out early next year features Kazran (during the time he travels with 11), so I may reconsider his status as a companion.
Adam Mitchell has two adventures linked by two stories, and he joined the TARDIS in a similar manner to other companions. Wilf did eventually get on board the TARDIS, but it was only very briefly and during 1 story.
I classify companions as characters that have had multiple consecutive adventures with the Doctor in more than one story. This includes people like Katarina and Adam, but exludes those like Wilf and Kazran.
Kazran Sardick has had multiple consecutive adventures with the Doctor, but they all happened during "A Christmas Carol." This is similar to Sara Kingdom who only has "The Daleks' Master Plan" on TV; however, Big Finish have multiple stories set during that story which heavily expand her role as a companion. "The Churchill Years" boxset coming out early next year features Kazran (during the time he travels with 11), so I may reconsider his status as a companion.
Adam Mitchell has two adventures linked by two stories, and he joined the TARDIS in a similar manner to other companions. Wilf did eventually get on board the TARDIS, but it was only very briefly and during 1 story.