PIP claimants receive up to £627 a month depending on how much their condition affects them and whether they qualify for both the daily living and mobility component.
However, thousands could have been receiving less than they were owed a court ruling found in August 2020.
After the ruling, the DWP changed how it considers whether someone can wash or bathe safely, as part of the PIP assessment.
Now, the DWP is conducting a review of PIP claims made by deaf or hearing impaired people who may be affected by this change – they could be owed up to £5,000 in back payments.
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