Home Instead Senior Care, Greenwich and Bexley, has been rated outstanding by the Care Quality Commission.
It becomes the only domiciliary agency throughout the two London boroughs to receive the rating.
The service got the commendation for being caring, responsive and well-led.
It was rated Good for being safe and effective, following an inspection, in March 2019.
The CQC confirmed the feedback it received from people was extremely positive throughout.
People using the service and their relatives expressed great satisfaction and spoke highly of staff and the services they provided.
One said: “I think Home Instead is the Rolls-Royce of care – absolutely no complaints. The level of care is brilliant.”
It also found how the care workers had an excellent understanding of people’s social and cultural diversity, values and beliefs.
Debbie Ivanova, deputy chief inspector, Adult Social Care, said: “The Home Instead group continues to provide exceptional care – and its domiciliary care provided in the London boroughs of Greenwich and Bexley is no exception.”
She added: “It was good to hear from people that used the service. One described it as the Rolls-Royce of care and on the evidence of this inspection, it is hard to argue with that view.”