Some good option for travellers in the UK looking for some reasonable solution to Mexico. Non-stop flights from London to Mexico City are now available already for £413 (€480). This is including travel dates over summer holidays 2017. Althought summer is not main tourist season in there you should still enjoy it (expect short rain showers in afternoon). Also flights in July / August are usually significantly more expensive. You can also depart from other airports in the UK with layover in London.
Current British Airways promotion is valid for bookings made till 21st of February or until sold out. Travel period is then throughout whole year 2017 including summer holidays. Max stay 12 months.
Booking samples
London - Mexico City for £460 (directly with BA, travel date sample 17.7. - 7.8.2017)
London - Mexico City from £413 (non-stop flight)
Travel dates.: Currently plenty of travel options are available for advertised rate. Flights over weekend are slightly more expensive. To compare lowest fares available you may check here with BA as they offer week´s view.
Booking sample of cheap non-stop flights from London to Mexico City over summer holidays 2017 for £413 here. In this case you would depart from the United Kingdom to Mexico on 17th of July 2017. Your return flight from this usually fairly expensive destination in North America back to London would be then on 7th of August 2017.