The Gulf carrier has increased its four-times-daily Heathrow-Doha service to five-times-daily.
It will continue to offer an additional daily London flight until the end of January.
Qatar has also increased flight frequencies on another 17 routes "to meet travel demand during the peak winter holiday season".
The airline is continuing to operate its flexible booking policy which allows travellers to make unlimited changes to their travel dates and destination.
It is also providing fee-free refunds for all tickets issued for travel completed by 31 May 2022.
