That 70s Show is set (obviously) in the 1970s, with the pilot taking place in 1976 and the finale New Years Eve 1979. However, despite this, it occasionally tends to feature elements from the '80s, '90s, and even the early 2000s, muddying the show's timeline in the process.
- A 1997 Ford Expedition is visible in the opening, on the right side of the Vista Cruiser (it also loops every few seconds).
- When the gang are in Canada, the RCMP detachment has a map of Canada with Nunavut. Nunavut became a territory in 1999.
- The RCMP officers are wearing Red Serge. The iconic Red Serge uniform was relegated to ceremonial wear in 1920 and was replaced by blue and brown uniforms for duty wear.
- Eric's room has flags of several countries that did not exist in the 1970s, such as Georgia and Estonia.
- In the pilot, the boys are looking at a Playboy with a perfect bound centerfold, not saddle stitched (stapled) as they were in the 70s.
- In the episode where Jackie gets a job at the Cheese House, Sophie's Choice is referenced. The book was published in 1979 and the movie was released in 1982.
- One episode has "Any Way You Want It" by Journey, released in 1980.
- In one episode, a Star Wars action figure with a green lightsaber is seen. Green lightsabers were introduced in Return of the Jedi in 1983.
- Though it is explicitly stated that the green lightsaber was a mistakenly made accessory for a Darth Vader action figure, commented to be very rare because only so many where made before the mistake was caught and fixed (a minor plot point, as Eric leaves it in the tub and mistakenly accuses his rival that season of stealing it due to its rarity). The story Eric comes up with when playing with it has a different lore, painting it as a more powerful version of Vader's normal Saber.
- Krispy Kreme donuts are featured throughout the series. Krispy Kreme came to Wisconsin in the 2000s.
- In one episode, Red is checking the mail. One is a credit card mailer, which has a credit card with a hologram. Holograms were introduced on credit cards in 1983.
- In the pilot, Coca-Cola bottles with printed red labels appear. In 1976, Coke bottles were full glass with the logo molded into the glass.
- In one episode, Kitty gives Fez and Hyde Snack Pack puddings in the modern plastic packaging. In the 70s, Snack Packs came in tin cans.
- In various episodes, cassette tapes with clear housings are used, introduced in 1984.
- A character's father is mentioned as working for Six Flags. The park, known as Six Flags Great America, north of Chicago and south of Milwaukee, was owned by Marriott and called "Marriott's Great America" until it was purchased by Six Flags in 1984, when it was renamed Six Flags Great America. And people still called it "Great America" anyway.
- Donna mentions Kelso melted Eric's G.I. Joe. Eric replies, "The Real American Hero deserves better." The phrase "The Real American Hero" was first used in the 1982 relaunch, G.I. Joe: A Real American Hero.
- Jackie wears a Rainbow Brite t-shirt. Hallmark introduced Rainbow Brite in 1983, and the first series episode aired in 1984. Hallmark licensed rights to Mattel, who first issued dolls, toys and other items in 1984. The first Rainbow Brite movie, Rainbow Brite and the Star Stealer, came out in 1985.
- In "Eric's Burger Job", set 1976, Kelso claims he mistook Donna's party for a toga party and recites the chant from Animal House, released in 1978.
- Beer cans are frequently shown with captive stay tabs. These did not come into common use until the 1980s. Cans in the 70s still had ring pull tabs.
- In the episode where the kids and Red go to a Green Bay Packers game, several of the extras wear team merchandise that was clearly made in the 2000s, including jerseys bearing the Reebok logo (which was the NFL's jersey sponsor from 2001-2011).
- Hyde has a Spider-Man pillow with the logo introduced in the early 90s.
