UK Part I vs SSR

UK Part I is full registration, needed over 24 m or for a registered mortgage. The Small Ships Register is cheaper, for UK-resident owners under 24 m.

Updated 24 Oct 2026 3 min read

Key points

Part I registration allows a mortgage to be registered. The SSR does not.
The SSR covers pleasure vessels under 24 m and requires UK residence.
Neither is the best proof of ownership. A bill of sale is.

Two UK registers

Part I (full registration). The UK Ship Register. Vessels over 24 m must use it. It allows registration of a mortgage and gives the boat British nationality for international purposes. The conditions on who can register have changed since Brexit, so check GOV.UK.
Small Ships Register (SSR). A simpler register for pleasure vessels under 24 m. Sources give a fee of about £25 and a five-year validity. The owner must be resident in the UK, with one source putting this at 185 days in 12 months.

What the register proves

Sources disagree on whether Part I proves ownership. The Institute of International Marine Surveyors states that Part I registration is not proof of ownership, and that the only legally recognised proof is a bill of sale. Forum posts say the same for the SSR. When you buy a UK-registered boat, rely on the chain of bills of sale, and check the register for mortgages. See Checking ownership and Liens, mortgages and encumbrances.

What it means if you buy a UK-flagged boat

Mortgage. A Part I boat may have a registered mortgage. Get it discharged at the sale. See Closing, paying off finance and de-registration.
SSR owners. An SSR boat can usually change hands without a mortgage check, so the lien check relies on documents and searches.
Eligibility. You may not qualify to keep the UK flag once you own the boat, especially if you live in the EU. Plan the new registration. See Transfer of ownership, flag change and de-registration.
VAT. The UK is outside the EU. See Buying a yacht from the UK after Brexit.

Checks before you buy a UK-flagged boat

Ask which register the boat is on, and for the certificate.
Ask for the full chain of bills of sale back to the first owner.
Ask the seller to confirm in writing that no mortgage or other charge exists, and check the register if it is Part I.
Ask where the boat has been since 2020, and get the VAT evidence. See Proving and verifying VAT status: which documents count, and checking before you offer.

Which is better

For a UK-resident owner with a leisure boat under 24 m and no loan, the SSR is simpler and cheaper. For a boat over 24 m, a boat with finance, or an owner who wants the strongest legal record, Part I is the route.

Also useful at step 3 Choosing a flag and registering your yacht

General information, not legal, tax or financial advice. Rules change; check your own case with a professional or ask us.