United Airlines via ShermansTravel offers select United Airlines Roundtrip Fares to Mexico and the Caribbean with prices starting at $186.03. (On the Shermans Travel landing page, click on "" in the main paragraph to see this sale.) This price is valid on flights departing on March 21 from Houston, TX, (IAH) with arrival in Cancun, Mexico, (CUN) and return on March 28. That's the lowest price we could find for select routes on United by at least $42, although they were a buck less a week ago (since expired). Book this travel deal by March 31.

All prices, dates, and booking details were valid at the time of publication.