Trivia

In the untranslated dialogue with the Dutch girl, Kris asks her what she wants for Christmas. She says she wants nothing, telling him she got her gift by being adopted by her new mother.

The cast and crew were unanimous in their opinion of Edmund Gwenn: they loved him. Alvin Greenman, who played Alfred, called him "a dear, dear man," and Robert Hyatt, who played Tommy Mara, Jr., said in a 2001 interview, "He was a really nice guy, always happy, always smiling. He had this little twinkle in his eye." Added Maureen O'Hara: "...by the time we were halfway through the shoot, we all believed Edmund really was Santa Claus. I've never seen an actor more naturally suited for a role."

When Edmund Gwenn accepted his Best Supporting Actor Oscar, he said, "Now I know there's a Santa Claus."

Both Macy's and Gimbel's were approached by the producers for permission to have them depicted in the film. Both wanted to see the finished film first before they gave approval. If either had refused, the film would have had to been extensively edited and reshot to eliminate the references. Fortunately, at the test viewing, both were pleased with the film and gave their permission.

The film was shot during a bitterly cold New York winter. On several occasions, the cameras literally froze. Maureen O'Hara remembered that a woman named Vaughn Mele lived across the street from where they were shooting exteriors and allowed the crew to warm up in her house. In gratitude, O'Hara took her and her husband to the famed "21" restaurant and she was so excited all she could drink was a glass of milk.