Are butterfly knives legal in Texas?

Per the Texas Penal Code, butterfly knives (aka balisongs) are legal to own, and as of September 1, 2013, they are legal to carry if the blade (measured from the handle) is no longer than 5.5 inches and only sharpened on one side. The bill that legalized the carrying of switchblades (including butterfly knives) was House Bill 1862 (83rd Regular Session of the Texas Legislature) by Rep. Harold Dutton.

As of September 1, 2015, Texas state law (Texas Local Government Code Section 229.001) also preempts municipalities and counties from creating or enforcing knife ordinances that are more restrictive than state law. The bill that added knives to the list of weapons (a list that already included firearms, air guns, and explosives) that municipalities and counties cannot regulate was House Bill 905 (84th Regular Session of the Texas Legislature) by Rep. John Frullo. This means that, with the exception of federal properties, butterfly knives are now legal throughout Texas.