This is correct. The Universal Law Formulation of Kant's Categorical Imperative states, roughly:

Act only according to that maxim whereby you can, at the same time, will that it should become a universal law.

In considering the maxim "Act so as to maximize total utility" (for some specific definition of utility), a Kantian would attempt to universalize it and ask "what would the world look like if everybody followed this maxim?" The merits of the maxim would then be judged against other possible maxims (or combinations thereof) by comparing the resulting worlds.

As a contrived example: A Kantian might consider the problem of "lawn crossing". Specifically, is it right or permissible to walk directly across the grass instead of taking the path around it? If we universalize this, then we have a world where everyone crosses the grass so the grass gets trampled and dies. The Kantian might then conclude that this world is inferior to the one where everybody takes the path around, therefore the Kantian would conclude that it is wrong for anyone to cross the grass.