Staff at George Ide, in Chichester, took on the challenge over the South Downs for Headway West Sussex.
The 13-strong team of amateur cyclists, used the ride as a way of marking the firm’s 50th year.
They managed to raise £7,500.
Paul Fretwell, a personal injury partner, said: ‘The work done by Headway West Sussex is incredibly important in offering support to head injury victims, their families, and their carers.
‘The ride itself was dogged by some pretty unpleasant weather, including torrential rain at one stage.
‘But everyone was determined to complete the course and a strong sense of purpose and enthusiasm kept us all going – despite the challenging conditions.’
Claire Watson, head of personal injury at George Ide and a HWS trustee, said: ‘This local charity makes a real difference to the lives of many brain injury sufferers and I am delighted that we are able to make a significant contribution to its valuable work.
‘Raising money for a cause that does so much for people throughout West Sussex helps reinforce awareness amongst the local communities it serves as well as providing much-needed funding for its essential activities.’
Go to headwaywestsussex.org.uk.