A combustor wall assembly has a heat shield and a supporting shell with a cooling cavity defined therebetween. A grommet generally includes a wall defining a dilution hole isolated from the cooling cavity, and a flange projecting radially outward from the wall and into the cooling cavity. The flange is space from the heat shield and a cooling channel is defined between the wall and the heat shield that communicates with the cavity for cooling the wall proximate to a combustion chamber.