This episode is the first appearance of Alice's boyfriend, Sam, the butcher.
On the phone, Jan tells her friend, "I don't see what's wrong with freckles! I got lots of 'em!" In season 2's "The-Not-So-Ugly Duckling", Jan rubs lemon juice on her freckles to try to get rid of them.
Although the Brady household has two telephones, in later seasons the phone in Mike's office/den appears in the living room, near the front door. The other phone stays in the same location on the family room counter until "A Very Brady Christmas" and the Brady Bunch spin-offs, when it becomes a push-button phone mounted on the wall.
The episode title is a reference to the phrase, "Sorry, wrong number".
Mike tells Carol that the extra money for the kids' phone calls will be $36 a month. $36 in 1969 is equal to about $302 in 2023.