What's the difference between NEC3 and NEC4?

The key differences between the two currently supported generations of NEC contracts.

What's the difference between NEC3 and NEC4?<br>

NEC4 changes and differences at a glance:

All of the changes made to the contracts are a direct result of feedback from industry. The style, layout, terminology and key project management processes that run through NEC3 contracts remain in NEC4, however - maintaining the clarity and ease-of-use that NEC is known for.

  • New forms of contract - the Design Build and Operate Contract (DBO), the Alliance Contract (ALC), and the Facilities Management Contract (FMC).
  • Improved clarity and simplicity across the suite.
  • New and improved support for dispute avoidance, early contractor involvement, quality management, and more.
  • Innovative new features and new contracts help users further achieve improvements to the efficiency and outcome of their projects and work programmes.

Why the need for NEC4?

In the 15 years between the release of NEC3 and NEC4, the engineering and construction industry made step change improvements in the way projects and work programmes are procured and delivered. It has been refreshing to see how the industry has innovated and improved, leaving behind a historical reliance upon traditional methods of procurement and limited forms of contract.

NEC has played a part in helping the engineering and construction industry do things differently and better. It has done so by, for example, introducing effective project management procedures

requiring pro-active management of risk and change, and the day- to-day use of an up-to-date works programme, into the contract itself. The ability to choose different pricing options (including target contracts and cost reimbursable contracts) has also given Clients flexibility in the allocation of risk, and the ability to share risk and jointly manage it, collaboratively.

NEC4 has taken the successful NEC3 contract suite and enhanced it, with some new features and some new forms of contract. All of the changes are a direct result of feedback from industry, to support methods and provide solutions which Clients are demanding.

Popular links

Looking for more information? Download the white paper, or try one of our introductory 'NEC3 and NEC4 compared' online training courses.

NEC4: The Next Generation<br>

NEC4: The Next Generation

Published in 2017, NEC4: The Next Generation white paper goes into more detail about the improvements made between NEC3 and NEC4, helping you to understand how NEC continues to stimulate good project management and a spirit of mutual trust and collaboration.

Read more


Learn in the classroom or online with NEC training. Whether you are new to NEC or an advanced practitioner, we have a range of training options covering your needs.

View Courses