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HMRC internal manual

National Insurance Manual

Refunds: Class 1: Primary NICs paid by employer but not deducted from employee

Regulation 52A(9), SS(C)R 2001

Generally, the employee must apply for any refund of primary NICs paid over the annual maximum. However, where the employer has made no deduction from the employee’s earnings in respect of those NICs and the year is closed, they may apply for the refund instead.