5. c. 51) was an act of the Parliament of the United Kingdom that consolidated and revised existing legislation that regulated local government in England (except the County of London) and Wales.

It remained the principal legislation regulating local government until the Local Government Act 1972 took effect in 1974.

Although local authorities acquired few new powers or duties, the Act did include a few innovations: Although the 1933 Act did not create new local government areas, it repealed most of the Local Government Acts of 1888 and 1894, and parts of the Municipal Corporations Act 1882, and reestablished the existing councils and administrative areas.

The councils for each of these various areas were to be known by the generic term of "local authorities" in this and subsequent legislation.

For example, many council byelaws now in force are made under section 249 of the Act.