Phasing out of the Assigned Formal Tonnage (AFT) method - SSB No.: 15/2023

Scope

This bulletin applies to owners of vessels less than 12m in length.

Purpose

This bulletin informs the stakeholders on the Assigned Formal Tonnage method being phased out as of July 1, 2026.

Background

The Assigned Formal Tonnage (AFT) method of Part 3 of the current Standard for the Tonnage Measurement of Vessels (TP 13430) applies to any vessel of less than 12 metres in length without any limitations. Since its introduction in 2012, the use of AFT resulted in an increased number of vessels’ designs of disproportional breadth and depth in relation to length. This resulted in a tonnage measurement which doesn’t represent the actual size of vessels.

What you need to know

Transport Canada will be publishing a new version of the Standard for the Tonnage Measurement of Vessels (TP 13430) in 2026.

This new version will remove the use of the Assigned Formal Tonnage (AFT) method which is currently being used as one of the options to determine the tonnage of vessels less than 12m in length. This change is happening because this method may potentially have increased safety risks and its results don’t accurately reflect a vessel’s size.

The amended TP 13430 (Standard for the Tonnage Measurement of Vessels) will be published 36 months after the date of publication of this Ship Safety Bulletin (SSB). As such, the date of application of the amended TP 13430 will be July 1, 2026.

As of July 1, 2026, Transport Canada will no longer accept the use of Assigned Formal Tonnage (AFT). This means that vessels can’t use this method if they register on, or after, July 1, 2026.

Vessel owners can still measure their boats themselves by following the simplified method of Part 3 of the Standard for the Tonnage Measurement of Vessels, or by hiring an appointed tonnage measurer.

Vessels that register before July 1, 2026 and use the Assigned Formal Tonnage (AFT) method can keep their tonnage unless the vessel is modified in a way that changes its tonnage by more than 5% after July 1, 2026.

If you are planning to modify your vessel, please consult tonnage specialists or Transport Canada in order to fully understand the potential implications on your vessel operations.

Keywords:

1. Tonnage measurement
2. Assigned Formal Tonnage
3. Vessel Registration

Questions concerning this Bulletin should be addressed to:

Contact us at: Email: marinesafety-securitemaritime@tc.gc.ca or Telephone: 1-855-859-3123 (Toll Free).