Charles Durning, who played Santa Claus, also starred in The Muppet Movie (1979), where Durning played the evil Doc Hopper.
When Snuffy is about to leave for Cincinatti, Big Bird's mittens and scarf are red. In the future on the 365th consecutive Christmas, Big Bird's mittens and scarf are black to represent his sadness.
"Keep Christmas With You (All Through the Year)" makes a return from Christmas Eve on Sesame Street (1978) 18 years earlier. Also returning are Bob McGrath as Bob, Sonia Manzano as Maria, and Roscoe Orman as Gordon, as well as a number of Muppet characters (though some of them no longer portrayed by their original Muppeteers).
Although Ernie and Bert appear, they do not have any discernable dialogue despite Steve Whitmire & Frank Oz already being in the cast as Kermit and both Cookie Monster and Grover.
The main premise about Christmas being every day is inspired by the 1892 story "Christmas Every Day" by William Dean Howells. Another adaptation of the same story, Christmas Every Day (1996) was released in 1996, the same year as "Elmo Saves Christmas."