Short answer. Yes. Under Article 106 the company you were deployed to is jointly and severally liable with your agency for the wages it failed to pay, to the extent of the work you performed under the contract. It does not matter that the agency issued your payslips.
What the law says
the employer shall be jointly and severally liable with his contractor or subcontractor to such employees to the extent of the work performed under the contract, in the same manner and extent that he is liable to employees directly employed by him
Labor Code, Article 106 — Contractor Or Subcontractor. Read the full provision →
Joint and several means you can look to either one
The point of the phrase jointly and severally liable is that you are not required to divide your claim or to exhaust the agency first. The whole of the unpaid amount can be demanded from the principal, from the agency, or from both together, and it is for them to sort out between themselves who ultimately carries it. That is deliberate. A manpower agency can be thinly capitalised, can dissolve, or can simply stop answering, and a worker holding a paper claim against an empty company has nothing. The principal is solvent, identifiable, and had the benefit of the work.
The liability is measured by the work you did there
Article 106 limits the principal's exposure to the extent of the work performed under the contract. So the company you were deployed to answers for the wages earned on that deployment, not for everything your agency ever owed you. If you were sent to several client companies through the same agency, each one is answerable for its own period. This is why the deployment orders, daily time records and job orders matter more than the employment contract: they are what tie a particular unpaid month to a particular principal.
The principal's good faith is not a defence
It is common for a principal to say it paid the agency in full, so the shortfall is not its doing. The article does not make liability depend on fault, on notice, or on whether the service fee was remitted. The obligation attaches because the work was performed under a contract for the principal's benefit. Whether the principal can recover from the agency afterwards is a matter between the two of them and does not delay or reduce what is owed to you. A contract clause between them shifting the risk cannot bind a worker who never signed it.
What to have ready
Identify the principal precisely, by the corporate name on the gate pass, the uniform, the client copy of your time records, or the purchase order under which your agency billed. Keep whatever shows the rate you were promised and the periods left unpaid. Where the agency has no real equipment or capital of its own and you were doing work directly related to the principal's main business, a further question arises — whether the arrangement is labour-only contracting, in which case the principal is treated as your employer rather than merely a co-obligor for wages.