In short. Subsidiary means answering in default of another party; joint and several means answering alongside them and for the whole debt. Where work is contracted out, the regimes most often triggered are joint and several: article 42.2 of the Spanish Workers' Statute for wage and Social Security debts, and article 42.3 of the Spanish Act on Infringements and Penalties in the Social Order (LISOS) in health and safety matters. The only relevant instance of subsidiary liability is article 168.1 of the General Social Security Act, and it falls on the owner of the works, only after insolvency. If the cover in your policy is drafted solely in subsidiary terms, it is worth checking whether it reaches a joint and several judgment.
In 2025 Spain recorded 164 fatal accidents during working hours in the construction sector, according to the advance figures of the Workplace Accident Statistics published by the Ministry of Labour and Social Economy. That figure includes non-traumatic events — heart attacks, strokes — which rarely give rise to a liability claim, so it does not translate into policy claims. What it does describe is the scale of a risk that almost never materialises within a single company: on a site, or at premises with concurrent contractors, there are usually several parties liable at once.
And that is where the problem starts. Because when several parties are liable, the question is not only who answers, but under which regime.
What is secondary (subsidiary) liability?
It is liability that requires you to answer in default of another party. The subsidiary debtor is not in the front line: it is drawn in only where the party primarily liable cannot pay, and normally after that party's insolvency has been declared. There is, therefore, an order of priority that the creditor or the claimant must respect.
It is worth fixing the other two concepts at the outset, because commercial usage of the term blurs them:
- Joint and several: you answer alongside another party. The claimant may proceed against any of the liable parties for the whole debt, without first exhausting any other route. Whoever pays may later seek a contribution from the others, but that is their problem, not the claimant's.
- Direct: you answer in your own right, without the liability of another party as an intermediate step. That is the position under article 1903 of the Spanish Civil Code, which requires damage to be made good not only for one's own acts but 'for those of the persons for whom one is answerable'. It is direct liability for the acts of others, not subsidiary liability, however much a third party may have caused the event.
The distinction is not academic. It determines who can be sued from day one, and with it the moment at which your company becomes a defendant.
Subsidiary, joint and several, or direct: the full map
This is the table that is rarely presented in full. Each row answers to a different statute, with its own regime, its own time limits and its own requirements.
| Situation | Regime | Provision | Conditions that trigger it |
|---|---|---|---|
| Contractor's Social Security debts | Joint and several | Art. 42.2 Workers' Statute | For the 3 years following completion of the engagement; only where it is the principal's own core activity; subject to the exemption in art. 42.1 |
| Contractor's wage debts | Joint and several | Art. 42.2 Workers' Statute | For the year following completion of the engagement; only where it is the principal's own core activity |
| Health and safety breaches at the principal's premises | Joint and several | Art. 42.3 LISOS | During the term of the engagement and only where the infringement occurred at the principal's workplace |
| Social Security benefits payable by the employer | Subsidiary, on the owner of the works or plant | Art. 168.1 General Social Security Act | Only where the employer liable is declared insolvent |
| Business transfer | Joint and several, on the transferee | Art. 168.2 General Social Security Act | Transfer of the undertaking |
| Damage caused by persons for whom one is answerable | Direct, for the acts of others | Art. 1903 Civil Code | Fault or negligence; not subsidiary |
| Benefits surcharge | Direct, on the infringing employer | Arts. 164.1 and 164.2 General Social Security Act | Failure of safety measures. Uninsurable |
| Breach of the construction subcontracting regime | Joint and several | Art. 7.2 of Law 32/2006 | Construction only |
Three readings of this table correct the errors we see most often.
Article 168.1 of the General Social Security Act is not joint and several liability of the principal. It is subsidiary, it falls on the owner of the works or plant, and it operates only after a declaration of insolvency against the employer liable. What is joint and several in Social Security terms is article 42.2 of the Workers' Statute. This is the sector's most widespread confusion.
Article 42 of the Workers' Statute does not cover damages for an accident at work. Its scope is wage and Social Security debts. The claim by an injured contractor's employee against the principal runs down a different route: articles 1902 and 1903 of the Civil Code and the duties in article 24 of Law 31/1995. Anyone sizing their exposure by reading article 42 alone is looking at the wrong risk.
'Own core activity' is a requirement, not an ornament. Without it there is no joint and several liability under article 42.2. It is heavily litigated and turns on the actual subject matter of the engagement, so it cannot be said that every contracted-out engagement generates joint and several liability. Nor can the opposite be said.
Do you know whether the cover in your policy responds to a joint and several judgment? Request a technical review of your wording.
So what does the contractors' liability section of your policy cover?
Corporate liability policies routinely include a section labelled 'contractors' and subcontractors' liability'. Its stated purpose is to cover liability attributed to the insured for damage caused by the firms it engages, with its own sub-limit, within the same wording that houses employers' liability or public liability.
The point to watch is the drafting. An accident involving a contractor is frequently resolved on a joint and several basis — article 42.2 of the Workers' Statute, article 42.3 of the LISOS — or through a joint and several judgment against the principal and the contractor in the civil or social courts, with no prior declaration of insolvency against anyone. If the section is drafted exclusively in subsidiary terms, requiring the insured's liability to be second in line, there may be a mismatch between what the judgment says and what the policy describes.
This is not a general statement about the market: cover depends in every case on the particular conditions of each policy. It is a specific point to verify in the wording, and there are three questions worth putting to the insurer in writing:
- Does the section cover the insured's joint and several liability, or only subsidiary liability in the strict sense?
- Does it require a prior declaration of insolvency against the contractor before it operates?
- What is its sub-limit, and how does it relate to the employers' liability sub-limit and to the main limit?
In the liability of the principal we set out the allocation of duties that lies behind these judgments.
What no policy can cover
There is one front that no amount of drafting will solve.
Article 164.1 of the Spanish General Social Security Act provides that, where the injury is caused by a failure of safety measures, the economic benefits are increased by between 30% and 50%, depending on the seriousness of the breach. Article 164.2 places that liability directly on the infringing employer and provides that it may not be the subject of any insurance, any agreement or contract to cover, offset or transfer it being void as a matter of law. Article 164.3 adds that it is independent of and compatible with liabilities of every kind, including criminal liability.
It is a statutory nullity, not a negotiable exclusion. We deal with it in detail in why the benefits surcharge cannot be insured.
The paperwork that underpins your defence
If the principal's exposure arises from a duty of supervision, the defence is built by proving that the duty was discharged. And it is proved with documents dated before work began.
Article 24.3 of Law 31/1995 imposes on anyone contracting out works or services forming part of their own core activity and carried out at their own premises a duty to monitor the contractor's health and safety compliance. Article 10.2 of Royal Decree 171/2004 spells out how: the principal must demand, in writing and before work begins, evidence of the risk assessment and the prevention plan for the works or service contracted, together with evidence that the information and training obligations towards the workers who will be involved have been met. The chain passes downwards: the contractor must require the same of its subcontractors.
One nuance is needed about another much-invoked document. The negative certificate of outstanding Social Security debts issued by the General Social Security Treasury, provided for in article 42.1 of the Workers' Statute, releases the requesting employer from Social Security debts where the non-extendable thirty-day period passes without the certificate being issued. It does not release them from wage debts, nor from liability for an accident. It is not a general shield.
What to ask for, in what order and how to file it is set out in coordination of business activities: paperwork and contractors' insurance.
We review the documentary chain and the drafting of the cover in the same exercise. Bring us your case.
The role of an independent broker
Two policies with identical limits and similar premiums can behave very differently in the face of a joint and several judgment, depending on how the contractors' and subcontractors' section is worded. That difference does not appear in the commercial proposal: it appears in the general wording, and only when it is read with the map of liability regimes to hand. As an independent brokerage registered with the Spanish DGSFP under reference J0140, we act on the client's mandate: we negotiate the wording and not only the price.
In a business with a subcontracting chain, the useful work consists of cross-checking three things: the map of engagements and how they sit against 'own core activity', the sub-limit of each section of the liability policy, and the documentary evidence that underpins the defence. When a claim arises, we represent the company before the insurer.
Frequently asked questions
What is secondary (subsidiary) liability? Liability that requires you to answer in default of another party: it is engaged only where the party primarily liable cannot meet the debt, normally once insolvency has been declared. The clear employment-law example is article 168.1 of the General Social Security Act, which makes the owner of the works or plant subsidiarily liable.
What is the difference between subsidiary and joint and several liability? Subsidiary liability has an order of priority: the party primarily liable comes first. Joint and several liability has none: the creditor or claimant may proceed against any party for the whole debt. In contracted-out work, the regimes most often triggered — article 42.2 of the Workers' Statute and article 42.3 of the LISOS — are joint and several.
Is our company liable for an accident involving a contractor's employee? It may be, but not through article 42 of the Workers' Statute, which is limited to wage and Social Security debts. The damages claim runs through articles 1902 and 1903 of the Civil Code and the duties in article 24 of Law 31/1995, and judgment may be entered jointly and severally against the principal and the contractor.
Does the policy cover the benefits surcharge? No. Article 164.2 of the General Social Security Act places it directly on the infringing employer and renders void any agreement to cover, offset or transfer it.
What documentation should we require from the contractor? What article 10.2 of Royal Decree 171/2004 requires: in writing and before work begins, the risk assessment and the prevention plan for the service contracted, plus evidence of the workers' information and training. The contractor's policy is not required by statute; your contract must require it.
Sources and legislation
- Royal Legislative Decree 2/2015, consolidated text of the Spanish Workers' Statute, article 42 (paragraphs 1, 2 and 3).
- Royal Legislative Decree 8/2015, consolidated text of the General Social Security Act, articles 164.1, 164.2, 164.3, 168.1 and 168.2.
- Royal Legislative Decree 5/2000, consolidated text of the Act on Infringements and Penalties in the Social Order (LISOS), article 42.3.
- Law 31/1995 on the Prevention of Occupational Risks, article 24 (paragraphs 1, 2, 3 and 5).
- Royal Decree 171/2004, implementing article 24 of Law 31/1995, articles 10.2 and 10.3.
- Spanish Civil Code, articles 1902 and 1903.
- Law 32/2006 on subcontracting in the construction sector, article 7.2.
- Ministry of Labour and Social Economy, Workplace Accident Statistics, January–December 2025 advance release.
This information is for guidance only and does not constitute binding advice. Cover, limits and exclusions are governed in all cases by the particular conditions of each policy. New Brokers Correduría de Seguros, S.L., registered with the Spanish DGSFP under reference J0140.
