Cheers
A full list of special holiday episodes
Set in the iconic Boston bar "Cheers," this classic sitcom follows the colorful regulars and employees as they navigate life, love, and libations.
The show aired 2 Christmas episodes, 1 Thanksgiving episode, and 3 Halloween episodes.
Christmas episodes:

Season 6, Episode 12
Christmas Cheers
Frasier, Lilith, Norm, Cliff, Rebecca, Carla, Woody, and Sam all have their own holiday plans and problems. Sam struggles to find a last-minute gift for Rebecca and hopes to find something appropriate yet affordable.

Season 11, Episode 11
Love Me, Love My Car
Woody's parents give him and Kelly a pet pig, but see it as Christmas dinner. Rebecca saves the pig and wants to buy it, but when Woody refuses, she sets it free. The pig is found by Carla, who turns it into a meal.
Thanksgiving episodes:

Season 5, Episode 9
Thanksgiving Orphans
Diane and the gang plan a Thanksgiving potluck at Carla's new home, but things don't go according to plan when some guests don't show up and an uninvited guest crashes the party.
Halloween episodes:

Season 3, Episode 4
Fairy Tales Can Come True
On Halloween night, Cliff meets his dream woman at the bar, but he's too afraid to see her again without his costume. Meanwhile, Sam and Diane go on their first non-romantic outing after their breakup.

Season 5, Episode 5
House of Horrors with Formal Dining and Used Brick
Carla discovers that the new house she recently purchased was built on top of a 17th-century prison graveyard, leading to a spooky Halloween night alone in the house. Cliff offers to keep her company and help her overcome her fears.

Season 10, Episode 7
Bar Wars V: The Final Judgement
The Cheers and Gary's Olde Towne Tavern gangs have a Halloween prank war. But when Gary announces he wants a truce due to high blood pressure, Sam doesn't believe him and continues to plot. Later, Gary is found dead.