Lucy and Ricky swap apartments with a couple downstairs; therefore, in most episodes they are in 3D (and thus on the same floor as the Mertzes), but in some they are in 4A and living upstairs from the Mertz's.

The Ricardo's are said to live in an apartment at 623 East 68th Street, which in real life would be located in the East River.

For an entire season, the closing credits list Wilbur Hatch conducting the "Dezi" Arnaz orchestra. He spelled it Desi.

In one episode (where Lucy thinks she won new furniture from the Home Show) Fred can be seen waiting for his cue to enter the bedroom when Ricky first enters the room.

In various episodes, Ethel is referred to as Ethel Roberta, Ethel Louise, and Ethel Mae.

When the Ricardo's are moving to the country, Lucy is standing for the last time in the apartment and talks about how she will miss the place since they lived in that apartment for 15 years. However they had only lived there for 4 years. Prior to that they were in the other apartment in the same building.

In "Lucy Does A TV Commercial" when Lucy comes onto the set drunk, you can see her waiting behind the set for her cue to come on.