Time and Material – Definition, Billing Model and Meaning in Project Business

Time and material is a billing model in project business in which a client pays for the actual working time delivered as well as resources or materials used.

In contrast to fixed price projects, the project price is not fully determined in advance. Instead, billing takes place on the basis of services actually rendered, usually based on hourly or day rates.

This model is frequently used for projects whose scope or requirements are not yet fully defined at the outset.

In the time and material model, client and service provider typically agree on:

• Hourly or day rates for different roles or qualifications
• Possible costs for materials or additional services
• Billing intervals, for example monthly

During the project, actual working hours are recorded and billed regularly.
Typical billing components include:

• Working hours of employees
• External services or subcontractors
• Project-related costs or materials

Precise documentation of services delivered is decisive here.

The time and material model is particularly suited to projects with high flexibility or unclear requirements. Typical areas of application include:

• Software development
• IT implementation projects
• Consulting projects
• Creative projects in agencies
• Research and innovation projects

In such projects, effort and requirements are often difficult to calculate precisely at the outset.

The time and material model offers various advantages for clients and service providers.

For clients:

• High flexibility in project requirements
• Adjustments possible during the project lifecycle
• Transparent billing based on actual services delivered

For service providers:

• Lower financial risk when projects change
• Fair compensation for additional services
• Better adaptation to dynamic project requirements

This makes the model particularly suited to complex or iterative projects.

Despite its flexibility, the model also brings some challenges. These include:

• Lower cost certainty for clients
• Higher effort for documentation and time tracking
• Possible disputes over effort and billing
• Difficult comparison between project proposals

Transparent service records and clear project communication are therefore particularly important.

Project management and PSA systems support companies in managing time and material projects. Typical features include:

• Time tracking for project services
• Assignment of working hours to projects
• Automatic creation of invoices
• Analysis of project costs and margins

Through these features, time and material projects can be documented transparently and billed efficiently.

The time and material model is a billing model in which projects are billed on the basis of actual working time and resources used. It is particularly suited to projects with unclear requirements or high dynamic, enabling flexible adjustment of project scope during the lifecycle.