A child-resistant flip-top closure including a base for engaging a container and a lid is hingedly attached to the base. A child-resistant locking mechanism inhibits opening of the flip-top closure. The mechanism includes at least one locking tab extending vertically upward from a portion of the lid and terminating in a locking lip. An actuation button is attached to the tab though a connecting rib so that the button is positioned laterally to the side of the tab. At least one barrier wall located adjacent to the actuation button, the barrier wall formed integral with the base and extending upward. The barrier wall includes a locking ledge formed on a rear side of the wall. The locking ledge is configured to engage the locking lip of the tab so as to provide an interlock between the lid and the base.