Yes, and Mason jars can be sterilized with boiling water by either pouring the water into them or submerging them in a pot of boiling water. Before you take the step of submerging the Mason jars in water, you need to ensure the jars have already reached room temperature. If the jar is cold, putting it suddenly into boiling water can cause it to break due to the sudden temperature change. For optimal results, put your jar in the hot water as it is heating rather than waiting till it boils