According to the Environment Agency:-
Householders can dispose of their waste cooking oil in their general household waste.
Waste cooking oils can be soaked into normal household rubbish or placed into rigid plastic containers. Small amounts of waste cooking oil could be soaked into bread as food for birds.
Some civic amenity sites have the facility to accept the waste cooking oil. Householders will have to contact their local authority to see if the facility is available in their area.