All Fours, also known as High-Low-Jack or Seven Up, is an English tavern trick-taking card game that was popular as a gambling game until the end of the 19th century. It is the eponymous and earliest recorded game in a family that flourished most in 19th century North America, notable other members being Auction Pitch, Pedro and Cinch, which competed against Poker and Euchre. Nowadays the original game is especially popular in Trinidad and Tobago, but a simpler variant has also survived in parts of England.

All four or All fours may refer to:

• All Fours (Bosse-de-Nage album)
• All fours (human position)
• All Fours (game)
• All-four (public transport)
• a concept in Commanding precedent