Many stroke patients with speech problems are being left isolated once they are discharged from hospital, campaigners say.
The NHS offers those with communication problems access to community support groups led by stroke specialists.
But the Stroke Association estimates 90% of patients in England who need such help are not getting it.
The government said extra money is being invested to improve services in the community.
About 150,000 people a year have a stroke, and about a third of survivors are left with a communication disability as a result.
Not all of the stroke sufferers will need long-term help, but for those who have lost the ability to speak or find it difficult to use and understand language, the NHS provides communication support therapy.
This is normally delivered in a group setting and led by a stroke specialist. The groups help patients improve their speech or develop basic sign language to allow them to communicate.
The Stroke Association, which runs most of the services for the NHS, found that just 1,300 people in England are accessing the care.
This figure represents just 12% of those who have severe communication difficulties.
The charity's report said the situation was a little better in Wales and Scotland, but improvements could still be made.
It said NHS trusts need to monitor the progress of stroke patients more carefully and ensure there were sufficient services to help them.
Joe Korner, of the Stroke Association, said: "We all need to communicate. Whether it's through speaking, a hand gesture or the blink of an eye, the ability to interact with others is crucial.
"The loss of these basic skills can leave stroke survivors feeling imprisoned and depressed."
The Department of Health said money was being invested in a range of counselling and support services.
A spokeswoman added: "We know that long-term support needs to be better coordinated."