British Airways and the German carrier Lufthansa both cancelled weekend flights to the Egyptian capital, citing security concerns. Lufthansa have since resumed their services. BA say they will maintain the cancellation for six more days.
The Foreign Office in London has warned of an increased risk of terrorism against aviation.
A BA spokesman said on Saturday: "We constantly review our security arrangements at all our airports around the world, and have suspended flights to Cairo for seven days as a precaution to allow for further assessment."
The airline normally runs one flight from Heathrow to Cairo and back again every day. Flights are scheduled to resume on Saturday 27 July.
Egyptair is continuing to fly twice daily between Heathrow and Cairo - and flights from UK airports to other parts of Egypt are running normally.
The Foreign Office warns that certain parts of Egypt are to be avoided by tourists. But Cairo is considered as part of a safer region. Travellers are simply warned to review Foreign Office advice before going there.
UK flights to and from Egypt were temporarily suspended in October 2015, following the explosion of a Russian airliner over the Sinai desert.