There is a reference to the Mass Effect series in the ambitions expansion. When using the time machine to travel to the future, your Sim appears in a crowd of people cheering about how a shepherd saved the galaxy from a 'huge ancient machine God threat.' Additionally, the futuristic outfits that can be obtained from the future highly resemble the Spectre armor found in Mass Effect.

If a Sim with the Investigator profession is on a stake-out, there is a chance that this Sim will reference the case of Bella Goth. Bella Goth first appeared as a playable character in the console version of The Sims. Later, in the Sims 2, she appears to be missing from her family's neighborhood, Pleasentview, and found with no memories in another neighborhood, Strangetown. This reference seems to be a plot-hole, however, as Bella appears as a child in The Sims 3; which is supposed to take place 50 years before the events of The Sims.

In the Into the Future expansion, there is a pre-made house called "Formerly the Plains Express household" with the members Fryderyk Rama, Lilah Turni and a Plumbot named Bend0. This is a reference to the show Futurama, specifically Planet Express, Fry, Leela, and Bender.

In the DLC world Roaring Heights, the School building seems to spell "SCHOOL OF COCKSUKRS" mirrored and upside-down.

In June 2010, several players noticed that a package file was attaching itself to other packages in The Sims 3. The file was a corrupted girl doll object titled "Girl Doll Dressed", which was incorrectly cloned from the Teddy bear. Game installations became "infected" by players downloading lots, houses or Sims with the hidden doll attached, similar to how computer viruses spread, and the doll was determined to cause longer loading times and game crashes. Players then unknowingly uploaded these infected packages to The Exchange, the game's online custom content workshop, causing it to spread to even more players.

Many Sims community sites began reporting the issue and one user posted a guide on how to manually remove the doll from the game to prevent the glitch from spreading, and a SimGuru on EA's official Sims forum eventually responded with a stickied post informing the community about the issue, and stated that EA would patch the game in the future to institute measures preventing corrupted objects from being uploaded to The Exchange.