Similar at first glance, far apart in practice: contract for work and mandate under the Swiss Code of Obligations. When which contract type fits — and why a wrong choice creates problems.
In the Code of Obligations, the contract for work (Art. 363 et seq. CO) and the mandate (Art. 394 et seq. CO) stand side by side. Both regulate services — but the difference in warranty and liability law is significant. The contractual label alone is not decisive; the court examines what the parties actually wanted and lived.
Contract for work — obligation of result
The contractor owes a specific result — a work. In the case of a defective work, the customer can choose between rectification, reduction of the price or rescission (Art. 368 CO). Notice of defects must be given shortly after discovery (Art. 367 CO); the limitation period for hidden defects is five years for immovable works (Art. 371 CO).
Classic contracts for work: construction, carpentry and installation work, software development with a clearly defined deliverable, translations with a defined output, printing assignments.
Mandate — obligation of diligence
The mandatee owes diligent activity, not a specific result. If the result does not occur, that is not a defect — provided the mandatee has worked lege artis. The principal can revoke the mandate at any time (Art. 404 CO), even if the mandate is bound in time.
Classic mandates: lawyer's mandate, medical treatment, tax advisory, asset management, mandates for translations without defined end product (e.g. interpreting services).
Where it gets critical: IT and consulting projects
Software, consulting and design projects fall into a grey area. Contractually often labelled as work contracts (with sprint goals, acceptance criteria), in practice often mandate-like (iterative adjustment, no final end product). In a dispute the Federal Supreme Court decides by actual content, not by label.
In a failed IT project, the customer almost always loses when the court qualifies the contractual relationship as a mandate and not as a contract for work — because the rectification rights are missing.
What to watch in contract drafting?
If a specific result should be owed: define concrete deliverables, acceptance criteria, acceptance procedure and warranty periods contractually — then the work-contract model is stable. If the result is open and the value lies in diligence: explicitly designate as a mandate and choose the fee model (hourly rate, flat fee) accordingly.
Waiver of the right to revoke at any time
Art. 404 CO is mandatory law. Contractual exclusions are void. Those who want to secure a longer commitment for the mandatee can however structure the contract as a contract for work or a mixed contract — provided the result component is real.