There are employment contracts that begin with an implicit promise: "it's only for a few months." The problem is that, as time passes, the worker stays, the company relies on them, a routine sets in, and suddenly the question arises that determines stability, rights, and... compensationSo, does this contract have an end date or could it become an open-ended contract?
A fixed-term contract with an indefinite term exists precisely for situations where a company needs to hire but cannot define an end date from the outset. However, "not knowing the date" does not mean "it can always be used." In Portugal, the term "indefinite" has its own rules, specific foundations, and limits. And when these rules are used incorrectly, the contract can be considered indefinite, with serious consequences.
In this article we explain what a fixed-term contract is, when it can be used, what clauses it should contain, what the worker's rights are, how termination, notice period and compensation work, and the most common mistakes that create conflicts.
What is a fixed-term contract with no set term?
A fixed-term contract with no defined end date is a fixed-term employment contract, but without a defined end date. Instead of ending on a specific day, it ends when a future, uncertain event occurs that justifies the hiring.
In practice, the company hires for a temporary need, but this need doesn't have a fixed schedule. The end of the contract is linked to the end of the reason for the contract: for example, the return of a replaced worker, the completion of a project, the end of a construction project, or the conclusion of a specific seasonal task.
The term is "uncertain" because the date is unknown. But the basis must be clear, real, and verifiable. If the basis is vague or if the need is not temporary, the contract loses its protection.
Fixed-term contract with uncertain term vs. fixed-term contract
The difference seems simple, but it has a huge impact.
In a fixed-term contract, there is a defined end date or duration. The company knows when it ends, and so does the employee.
In a fixed-term contract, there is no end date. There is an event that terminates the temporary need.
What does this change in real life?
- In managing employee expectations, there is no such thing as a specific "Day X".
- In the employer's legal management, this is because they have to prove the temporary need and the termination event.
- In termination proceedings, the communication of the termination becomes especially important.
If you want to understand the overall landscape of contracts, you can supplement this with... Types of employment contracts.
When is a fixed-term contract of uncertain duration permitted?
A fixed-term contract is not a "trick" to avoid open-ended contracts. It can only be used when there is a duly justified temporary need.
The most typical scenarios in practice include:
- Replacing an absent worker when the return date is unknown (prolonged illness, parental leave, secondment).
- Replacing a worker who is leaving with an uncertain departure date, for example, during a complex recruitment process.
- Execution of a temporary task or project without a fixed deadline, such as construction work, system implementation, or a specific campaign.
- An exceptional increase in activity where the duration cannot be precisely predicted.
The crucial point is this: the reason must be temporary. If the function is permanent and the position is structural, the concept of an uncertain term is at risk.
The obligation to provide written justification
This is where one of the most costly mistakes begins.
In a fixed-term contract with no set end date, the justification must be written and concrete. "Company need" is not enough. "Increased workload" without explaining what it is, why, and in what context, is also weak.
A strong rationale should explain:
- What is the temporary need?;
- why is it temporary;
- The link between the worker's needs and their function;
- What event will mark the end?.
When the justification is vague, the subsequent discussion becomes simple: the worker says the position was permanent, and the company cannot prove otherwise.
Essential clauses in a fixed-term contract of uncertain duration.
A fixed-term contract with an uncertain term can be short, but it cannot be loose.
In practical terms, it should contain:
- identification of the parties;
- workplace;
- category and functions;
- compensation and components;
- Work schedule and work regime;
- start date;
- explicit indication that it is for an uncertain term;
- concrete basis of the term;
- reference to the event that determines the expiration;
- Termination notification rules.
The clearer the wording, the less room there is for conflict.
Duration and limits: can it last forever?
No. And this is one of the most dangerous confusions.
Although the date is uncertain, the term is not unlimited. The law provides maximum limits for this type of contract. When the limit is exceeded, the contract may become an open-ended contract.
Furthermore, even before reaching the limit, if the company keeps the worker performing permanent duties, or if the temporary reason has already ended and the relationship continues, the risk of conversion increases.
The practical message is simple: the term "uncertain" must have a short lifespan in the legal sense, even if the date is not set.
Employee rights under a fixed-term contract of uncertain duration.
A fixed-term contract is still an employment contract. The worker has the same labor rights as any other employee, including:
- compensation and receipts;
- vacation pay, vacation allowance, and Christmas bonus;
- Protection during parenthood and illness;
- Rules regarding work and rest time;
- occupational health and safety;
- protection against harassment and discrimination.
The fact that it is "fixed-term" does not reduce basic rights. What changes is the way it is terminated and, in certain cases, the compensation at the end.
If you have questions about termination initiated by the employee, you can see Termination of contract by the employee: what are their rights and how to proceed?.
How does a fixed-term contract of uncertain duration end?
A fixed-term contract of uncertain duration expires when the reason that justified it ceases to exist.
Simple examples:
- The replaced worker returns;
- The work is finished;
- The project is completed;
- The exceptional peak of activity is ending.
But note: it's not enough for "the company to think" it's finished. There has to be a real correspondence with the written justification.
Furthermore, the company has communication responsibilities. The closure should not be a last-minute surprise without proper planning.
Notice period upon expiry: what does the employer have to comply with?
In practice, the termination of a fixed-term contract requires prior notice to the employee, with the notice period varying depending on the duration of the relationship.
The purpose of prior notice is to provide the worker with a minimum level of predictability, even in a contract without an end date.
When the notice period is not fulfilled, there may be consequences, including payment of compensation corresponding to the missing period.
If you are analyzing a termination and suspect irregularities, it may be useful to frame the issue within the context of default and evidence in Breach of contract: what to do legally.
Compensation for expiration: does it always exist?
In many cases, there is a right to compensation when a fixed-term contract expires.
The amount depends on applicable legal rules and the length of employment. The important point is this: compensation is not a "bonus." It's a way to balance the instability of a fixed-term contract.
When a company terminates a contract without respecting procedures, or when there is discussion about converting it to an open-ended contract, the issue of compensation may intersect with other forms of indemnification.
Conversion to an open-ended contract: when the uncertain term ceases to be valid.
This is the most relevant topic for many people.
A fixed-term contract of uncertain duration can be considered an open-ended contract when:
- There is no valid basis or the basis is insufficient;
- The reason given is not temporary;
- The contract exceeds legal limits;
- There is a renewal or continuity of functions beyond the reason;
- There is abuse of this figure to cover permanent needs.
In practice, the conversion could mean that, to terminate the relationship, the company would have to follow dismissal rules with justification, or negotiate an agreement, and not just declare "expiry".
This is one of the areas where the analysis of documents and the reality of daily work is crucial.
What should you do if you suspect your open-ended contract is illegal?
If you are a worker and suspect that the contract was used for a permanent need, the first rule is simple: do not act on impulse.
A prudent path leads through:
- Compile the contract and addendums;
- Keep job descriptions, emails, and evidence of ongoing tasks;
- Map dates: start date, job changes, and continuation after the reason for the change ends.;
- verify if there was formal communication regarding the grounds and the event of termination;
- Seek legal advice before signing any departure documents.
If you're being pressured to sign, you risk losing leverage. Signing closes doors.
What should you do if you are an employer and want to safely use an uncertain term?
From the company's perspective, the goal should be prevention, not remediation.
Safe use involves:
- Choose an uncertain term only when the reason is truly uncertain and temporary;
- Write concrete and verifiable justifications;
- Align functions with the purpose and prevent the worker from being a permanent "stopgap";
- Control deadlines and limits;
- Prepare the notice of expiry in advance;
- Keep proof of the event that justifies the termination.
Document management is part of the risk. When a company cannot prove its worth, it loses strength.
Uncertain term and unemployment benefits: what usually happens?
Many people associate indefinite-term unemployment with automatic access to benefits. In practice, access to benefits depends on requirements and qualifying as involuntary unemployment.
The key point is that termination due to a fixed term, when it occurs under legal terms, tends to be seen as termination initiated by the employer, which, as a rule, is more compatible with involuntary unemployment than termination by the employee.
However, each case depends on evidence and context, so it is wise not to decide solely based on hearsay.
Common mistakes that create conflicts
There are recurring errors in fixed-term contracts.
- A generic foundation with no real connection to the functions.
- Use of the term "uncertain" for permanent functions.
- Lack of proof of the cessation event.
- Lack of prior notice of expiry.
- The worker's continued employment after the supposed end of the reason for the job.
- Confusing addendums that attempt to "patch up" what started badly.
Avoiding these mistakes is cheaper than arguing about them later.
Conclusion
A fixed-term contract with no defined end date is a legal tool for temporary needs without a defined end date. It is not a shortcut to keeping workers in permanent instability.
When used correctly, it protects both the company and the worker with clear rules. When misused, it can turn into an open-ended contract, create opportunities for compensation claims, and transform a simple termination into a lengthy conflict.
If you have any questions about your contract, the legality of an open-ended contract, notice period, compensation, or conversion to an indefinite-term contract, talk to our team. CSG Lawyers and address the issue rigorously.
If you are looking for a attorney To analyze documentation, guide your position, and determine the best course of action, we are available to help.
