Economy awards from Boston (BOS) to London Heathrow (LHR) are currently bookable through United MileagePlus for 40,000 miles each way, with minimal taxes of just $6. Travel is available on August 13, 2026, and there's plenty of availability showing right now.
This is a notable discount from the typical rate of around 60,000 miles you'd normally see for transatlantic economy awards on this route. That savings of 20,000 miles per ticket adds up quickly for a family of four.
August is peak summer travel season for families heading to Europe, so finding award space at a reduced rate during this window is worth acting on. London in mid-August offers mild weather and plenty of kid-friendly attractions before the school year starts.
One practical tip: if you're flexible by a day or two, search nearby dates as well. Award pricing on United can shift, and you may find additional options at the same saver rate.
How to book
Search and book directly through United's award search tool: https://www.united.com/en/us/book-flight/united-awards/search