Yes and no.

On the one hand, they claim that there is no immortal soul, that after their death humans are kept in so-called “memorial tombs” until the day of their resurrection. On the other hand, they claim that their deceased elite members would live on in heaven as “immortal spirits”. But if there are no immortal souls – then what are these “immortal spirits”?

(What Does the Bible Really Teach?” page 72; “Pay Attention to Daniel’s Prophecy!” page 146, Watch Tower Bible and Tract Society)

(see The Wicked Little Horn)

Basically, the “memorial tombs” of Jehovah’s Witnesses are freezers for souls and the “immortal spirits” are active, non-frozen souls in heaven.
But this is something that Jehovah’s Witnesses have not yet realized.