The couple have invited close friends and family to an intimate gathering in the Los Angeles-area on Saturday. The date marks four years since they tied the knot on a private island in Fiji in a ceremony attended only by the barefoot bride and groom.
The pair, who have been seen on their show Tori & Dean: Home Sweet Hollywood having blow-out fights, have downplayed any talk of a split. Appearing on the The Ellen DeGeneres Show last month Spelling said, "There is no divorce in our future, at all."
McDermott and Spelling met in the summer of 2005 while in Canada filming the TV movie Mind Over Murder. They are parents to Liam, 3, and Stella, who turns 2 this summer.
Spelling will return to the bookshelves in June with her third book, tentatively titled uncharted terriTORI.
Reporting by PERNILLA CEDENHEIM