Fixed Price Contract

What is a Fixed Price Contract?

A Fixed Price Contract (also called a lump sum contract) is an agreement where the supplier commits to delivering the full scope of work for a predetermined price. The price remains the same regardless of the supplier’s actual costs — if costs come in under budget, the supplier benefits; if costs overrun, the supplier bears the loss.

How Does a Fixed Price Contract Work?

The key elements of a fixed price arrangement are:

• Defined scope — the Statement of Requirements must be clear and complete, since the price is based on it
• Agreed price — a total price (or schedule of prices) is set at contract execution
• Risk allocation — the supplier carries the risk of cost overruns; the agency has cost certainty
• Variations — any changes to scope are managed through a formal variation process, which may adjust the price

When is a Fixed Price Contract Used?

Fixed price contracts are appropriate when:

• The requirements are well-defined and unlikely to change significantly
• The scope of work is clear and can be accurately estimated
• The agency wants cost certainty and budget predictability
• The work has been done before — the supplier can draw on experience to estimate accurately

Common examples include construction projects with detailed designs, supply of standard goods, and well-defined IT implementations.

Fixed Price vs Other Contract Types

• Period Contract — covers ongoing services over time, often with rates rather than a single fixed price
• Cost-reimbursement contracts — the agency pays actual costs plus a margin (rare in Australian government procurement)
• Time and materials — the agency pays for actual hours and materials used (common for advisory work under Panel Contracts)

Tips for Tenderers

• Price accurately — the biggest risk in a fixed price contract is underestimating costs. Include adequate contingency.
• Understand the scope thoroughly — ambiguity in the SOR is a risk you carry in a fixed price arrangement.
• Manage variations formally — if the scope changes, ensure it is documented and priced before commencing additional work.
• Build in risk margin — but do not overprice, or you will lose on Value for Money assessment.