NHS Number Checker
The format for the new NHS Number adopts ten digits. The final digit is used as a check to validate the first nine digits. Validation is achieved using the Modulus 11 algorithm. Four steps are involved in applying the Modulus 11 algorithm to calculate the last digit. These are:
STEP 1 - Starting from the left, multiply each of the first nine digits by (11 - digit position). For example contents of digit position 1 would be multiplied by 10, contents of digit position 2 by 9, contents of digit position 3 by 8, etc.
STEP 2 - Add the results of the nine multiplications together.
STEP 3 - Divide the total by 11 and obtain the remainder.
STEP 4 - Subtract the remainder from 11 to get the calculated check digit. If the calculated check digit is 11, substitute a value of 0. If the calculated check digit is 10, then the first nine digits are invalid and are not to be used.
Why not try entering a NHS Number in the field below to check its validity? A valid number would be 401 023 2137.