About us

The MAIB investigates marine accidents involving UK vessels worldwide and all vessels in UK territorial waters.


Our job is to help prevent further avoidable accidents from occurring, not to establish blame or liability.

Marine Accident Investigation Branch receives between 1500 and 1800 reports of accidents of all types and severity each year. On average this leads to 30 separate investigations being launched.

Who we are

We are an independent unit within the Department for Transport. Our 4 experienced accident investigation teams are supported by an administrative team. We’re based in Southampton and have 35 members of staff.

Short video about MAIB:

The role of MAIB

This film tells how a ferry disaster led to the formation of the branch:

About Us

The second of our short films looks at how our inspectors operate in the field:

The role of MAIB inspectors

More information about the work of MAIB can be found in our information leaflets.

Our responsibilities

We’re responsible for:

  • carrying out investigations to determine the causes of accidents at sea
  • publishing reports that include our recommendations on improving safety at sea and the actions we’ve taken
  • increasing awareness of how marine accidents happen
  • improving national and international co-operation in marine accident investigations

Our priorities

Our priorities are to:

  • maintain our position as one of the world’s leading safety investigation organisations
  • help set standards in marine accident investigation by following best practice and asking those we work with to do the same
  • provide our staff with regular specialised training to keep expertise up to date

Regulations and guidance

Reporting requirements

Merchant Shipping (Accident Reporting and Investigation) Regulations 2012

The Merchant Shipping (Accident Reporting and Investigation) (Amendment) Regulations 2013

The Merchant Shipping (Accident Reporting and Investigation) and the Railways (Accident Investigation and Reporting) (Amendment) (EU Exit) Regulations 2018

Click here to report an accident page.

Marine guidance notice

MGN 564: marine casualty and marine incident reporting

Relevant extracts from the Merchant Shipping Act 1995

259. Powers of inspectors in relation to premises and ships

260. Provisions supplementary to section 259

267. Investigation of marine accidents

292. General functions of Secretary of State

Corporate information

Access our information

Jobs and contracts

Read about the types of information we routinely publish in our Publication scheme. Our Personal information charter explains how we treat your personal information. Read our policy on Social media use.