You are defined as a 'mariner' if you are or have been employed under a contract of service as:
We have a special unit to advise mariners about National Insurance contributions. If you need additional information, you can contact us. If you want you can email us.
Or you can write to us at this address:
Marine NICs
HMRC
15th Floor North wing
Ty Glas Road
Llanishen
Cardiff
CF14 5FP
You can also telephone us on 02920 326821 (or +44 (0)29 2032 6821 for international dialing).
To help us to advise you about your personal contributions position we will ask you to complete a questionnaire giving information about you and the ship you work on.