When you work with temporary agency workers in the Netherlands, it is important to understand the ABU phase system. This system, set out in the Collective Labor Agreement for Temporary Agency Workers, defines how temporary agency work develops over time.

The ABU phase system moves from a flexible entry phase to fixed-term contracts and, eventually, an indefinite or permanent secondment structure. For employers, this affects contract type, planning, payroll, labor conditions, sick leave arrangements, and long-term workforce decisions.

At Undutchables, we help employers use temporary employment and secondment solutions in a clear and practical way. Below, we explain the three ABU phases, the contract types you may see, and the main points employers should keep in mind.

The Three ABU Phases

The ABU phase system consists of three phases:

• Phase A: Entry, up to 52 worked weeks
• Phase B: Fixed-term succession, maximum 3 years
• Phase C: Indefinite or permanent secondment

In general, the longer a temporary agency worker works through the agency, the more employment security they build up. This gives employers flexibility at the start, while also creating a clear structure for longer assignments.

Because CLA rules can change, employers should always check the latest applicable ABU CLA or ask for advice before making contract decisions.

Phase A: Entry, Up to 52 Weeks

Phase A is the entry phase for temporary agency workers. It lasts a maximum of 52 worked weeks.

During Phase A, agencies may use different contract models depending on the assignment. Employers may come across the following contract forms:

• Agency work employment contract with agency clause, on-call
• Agency work employment contract with agency clause, not on-call
• Agency work employment contract without agency clause, on-call, secondment / Phase A

An agency work employment contract with an agency clause gives the most flexibility. If the assignment at the client ends, the temporary agency contract can also end. The agency clause also allows the temporary worker to stop working at any time during the assignment.

An on-call contract is usually used when working hours may vary. A not-on-call contract is more suitable when fixed hours are agreed for the assignment period. A secondment-style contract in Phase A can be used when the worker is supplied for a specific assignment.

For employers, Phase A is useful when the staffing need is temporary, flexible, or still developing. It is important to choose the contract form that matches the actual assignment and to communicate clearly with the worker about hours, duration, and what happens if the assignment ends.

Phase B: Fixed-Term Succession, Maximum 3 Years

When the worker moves into Phase B, up to six fixed-term contracts may be offered within a maximum period of three years.

Contracts in Phase B usually have fixed hours and defined terms. This phase gives the worker more employment security than Phase A and requires more planning from the employer and the agency.

For employers, Phase B means keeping track of contract duration, the number of contracts, working hours, payroll obligations, and possible next steps. It is also the moment to consider whether the role is still temporary or whether it is becoming a more structural part of the team.

Sick leave rules and other labor conditions continue to apply according to the ABU CLA and the arrangements agreed between the agency and the client.

Phase C: Indefinite or Permanent Secondment

After Phase B, the worker enters Phase C if the cooperation continues. In Phase C, the worker may receive an indefinite or permanent secondment contract, depending on the arrangement.

This phase offers the highest level of employment security within the ABU phase system. The contract no longer has a fixed end date, and the usual benefits, pension rules, and sick leave arrangements apply according to the ABU CLA.

For employers, Phase C is relevant when a worker remains in the assignment for a longer period and there is an ongoing need for their work. At this stage, it is important to review whether the current structure still fits the business need or whether another hiring solution would be more suitable.

Key Labor Conditions and Entitlements

The ABU CLA also sets out important labor conditions and entitlements for temporary agency workers. These should be applied correctly and recorded in payroll and personnel administration.

Key points include:

• Holidays: temporary agency workers are entitled to holidays according to the applicable CLA rules
• Holiday allowance: temporary agency workers are entitled to holiday allowance
• Pension: pension accrual is arranged through the applicable pension scheme for temporary agency workers
• Sick leave: coverage depends on the contract type and the applicable CLA provisions
• Agency clause: if present, assignment end rules should be clearly explained and documented

For employers, the main point is simple: labor conditions should be clear from the start. This helps prevent confusion and supports a professional working relationship between the worker, the agency, and the client.

Practical Implications for Employers

The ABU phase system is not only an HR or payroll topic. It also affects workforce planning and contract decisions.

Employers should pay attention to:

• Planning workforce flows around the 52-week and 3-year thresholds
• Choosing the right contract form in Phase A
• Tracking worked weeks and the number of fixed-term contracts
• Applying ABU CLA rules correctly for holidays, holiday allowance, pension, and sick leave
• Making sure the agency clause and assignment end rules are clearly explained
• Communicating clearly with the worker about contract type, hours, and next steps

Good tracking and clear communication help employers avoid surprises and manage temporary agency work in a compliant and practical way.

Need Help Implementing the ABU Phase System?

The ABU phase system can feel technical, but it does not have to be confusing. With the right support, it becomes a practical framework for managing temporary employment and secondment in the Netherlands.

Undutchables can help you choose the correct contract type, manage onboarding and payroll, and apply the relevant ABU CLA rules throughout Phase A, Phase B, and Phase C.

Depending on your situation, we can support with:

• Selecting the right temporary employment or secondment setup
• Explaining how the ABU phase system applies to your assignment
• Tracking phase transitions
• Preparing placement and contract documentation
• Coordinating payroll and onboarding
• Applying relevant labor conditions
• Advising on next steps when an assignment continues longer than expected

Ready to discuss temporary employment or secondment options? Get in touch with Undutchables and let us help you find the right solution for your organization.

It is important to know what your rights are with a company in the Netherlands. We hope we have been able to provide you with some insights through this article. For a complete overview of the ABU phase system, you can download our product sheet on this page. If you would like to know more, please contact us. Do you want to know more about what outsourcing recruitment can mean for you? Then read this blog.