What makes seafarers & mariners different from an ordinary filing?
Ships have their own treaty article, and it usually allocates crew income by reference to the enterprise operating the ship rather than the waters sailed. Days at sea are also treated differently from days in a country for most residency tests. An ordinary preparer applies the general rule and stops there, which is how the relief in the specific provision goes unclaimed.
Can you work with my existing accountant?
That is how most of these engagements run. They keep the domestic file, we take the cross-border piece, and the boundary is agreed in writing so nothing is done twice or missed.
When should I start my return if I sign off in the autumn?
Start while you are still aboard rather than after you land. The documents that take longest to obtain are the ones only the operator or the manning agent holds, and a request made from the vessel is usually answered faster than one made months later by someone no longer on the crew list. Everything else follows a fixed order: sea-time record first, then payroll and deduction certificates, then the treaty allocation, then the returns. If the record is assembled before you sign off, the filing itself is a short piece of work rather than a scramble.
Can I file while I am at sea on contract?
Yes. Documents can be exchanged on secure cloud software and signed electronically, so a contract at sea does not have to stop a filing, provided the practical limits are planned for. Connectivity aboard is intermittent and shore leave is short, so we agree in advance which items need your signature, get them to you in one batch rather than in a trickle, and do the preparation while you are unavailable. The part that genuinely requires you is small if it is organised. The part that requires the operator's records should be requested before you sail.
Which country's return do I file first?
As a rule the one with the primary taxing right, because the other return depends on it. Where your home country taxes you as a resident and gives credit for the tax the other country was entitled to charge, that credit cannot be computed until the first liability is quantified. Filing them in the wrong order tends to produce a home return carrying an estimated credit, which then has to be amended once the real figure arrives. Preparing both together, and filing in dependency order, avoids the amendment entirely.
What should I collect during the year rather than after it?
Four things, and all four are easier to get while you are aboard. The sign-on and sign-off dates as they happen, rather than reconstructed later from memory. The crew contract naming the operating enterprise, not just the agency you deal with. Each payslip or payroll summary as it is issued. Any certificate of tax deducted, which agents often issue once and do not reissue. A seafarer who lands with those four has a filing. One who lands without them has a reconstruction exercise before the filing can start.
Can someone file for me while I am away at sea?
Only if the authorisation is in place before you sail, which is why it belongs on the pre-contract list rather than the post-contract one. Each tax authority has its own form of representative authorisation and its own processing time, and none of it can be arranged usefully from a vessel with poor connectivity a week before a filing is due. Put the authorisations in place while you are ashore and the next contract does not interrupt anything. Leave them, and the whole calendar depends on when you next reach a port with a signal.
What happens if my contract runs across two tax years?
The pay is split at the year end and each part is reported in the year it was earned, which sounds obvious and is the single most common source of error in crew files. Payroll summaries are frequently issued by contract rather than by tax year, and the two do not line up. The sea-time record is what lets the split be made properly, period by period, rather than by dividing a contract figure across months. Where the two countries involved use different year ends, the same pay has to be split twice, on two different boundaries.
What happens if I have not filed for several years?
Missed years are handled as one package, not one at a time, because the route chosen for the first year determines the relief available for the rest. Each country has a disclosure or relief programme with its own conditions, and entering the right one — before the authority contacts you — is usually what keeps penalties down. Filing quietly outside a programme forfeits that protection. See catching up on missed returns.
How do I actually stop being taxed twice?
In this order. Fix your residence under each country's own rules, and if both claim you, apply the treaty tie-breaker. Identify where each type of income is sourced. Read the article that covers that income type, because it decides who taxes and at what maximum rate. Then claim the relief on the residence-country return, with proof of the foreign tax. Most of the tax people lose to double taxation is lost at the last step, not the first. See how double taxation is relieved.
