Do Microwaves Have To Be Vented? Yes, always 33% In most cases 16% In some cases 33% Not sure 16% Get Free Quotes Today! Question: Do Microwaves Have To Be Vented? Top Answer (33% of 6 votes): In some cases. Answer: Yes, always Explanation: Microwaves can be vented internally or externally. Advantage Repair Services, LLC Get Free Quotes Today! Find Local Pros Free Microwave Oven Installation Cost Estimates Related Questions How Much Is It to Install an Over-the-Range Microwave? Should a Microwave Be On Its Own Circuit?Top answer: In some cases How Much Does Microwave Installation Cost? Who Installs Gas Stoves? Who Installs Gas Lines for Stoves?