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HMRC internal manual

National Insurance Manual

Special cases: Class 1 - mariners: DL prescribed secondary contributor

Regulation 122 SSCR 2001

Liability to pay secondary Class 1 NICs rests with the employer. If the employer of a mariner does not satisfy the residence or place of business conditions NIM29009 but the person who actually pays the mariner does satisfy the conditions then that person is treated as the secondary contributor.