The 22-year-old Poirier is a perfect 3-0 since dropping down to featherweight. He most recently defeated Pablo Garza via second-round submission at UFC on Fox last month.
Lamas (11-2) was also victorious at UFC on FOX, defeating Cub Swanson via second-round submission, as well. The 29-year-old Chicago-native is 2-0 since dropping down to 145 pounds earlier this year.
UFC 143, headlined by Nick Diaz vs. Carlos Condit, will air live on pay-per-view. Other fights announced for the card are Josh Koscheck vs. Mike Pierce and Roy Nelson vs. Fabricio Werdum.