The guide 4. Manage delivery

Manage contract changes

Work with your supplier to manage any changes during the contract

Why it's important

Changes during a contract are often necessary, particularly in the case of complex technology projects where there may be a need to adapt and iterate how outcomes are delivered. Any contract changes need to be managed carefully to ensure that you avoid any legal or corruption risks.

What it means

What you can and can’t change during a contract will be informed by the terms and conditions agreed with the supplier. In outcomes-based contracts, appropriate changes are allowed providing that:

  • the supplier still delivers the outcomes you defined
  • there is no impact on value for money for your organisation
  • the changes fall within any contingency margin, for example when extending a contract length by a certain percentage

It may still be possible to make more significant changes providing that you:

  • agree the change in writing with the supplier
  • approve any change in budget with senior stakeholders
  • assess any impact on services for end-users
  • publish details of the changes online

If your requirements change significantly, so that they’re no longer covered by the original scope of your contract, you should cancel the contract and start the buying process again. This is so:

  • you can find a service that meets your requirements at the best price
  • suppliers who might be more suited to the work have a fair chance to apply

Do's and don'ts


  • be aware of any risks caused by contract changes
  • agree changes in writing with your supplier
  • keep evidence of any contract changes in case of disputes and to maintain an audit trail


  • do not allow contract changes that go significantly beyond the scope of your original requirements