Social Security on Contracting Agreements and Clearance Certificates

In contracting files, the largest liability rarely comes from tax — it comes from social security on the contracts themselves. This is written for contractors and for the principals who award work: how contract contributions are assessed, what the five percent retention under Article 38 actually protects, and how a clearance certificate is obtained without months of delay.

Article 38 is the whole structure

Article 38 of the Social Security Act provides that where work is awarded on a contracting basis, the principal must bind the contractor in the agreement to insure its workforce and pay the full contribution. To secure that undertaking, the principal must retain five percent of the total contract value and must not release the final instalment until the contractor produces a clearance certificate.

The point principals usually miss is that this provision does not transfer liability — it adds to it. If the contractor fails to pay and you did not make the retention, the organisation collects from you. At that stage, "they were his workers, not mine" is not an argument.

Coefficients: labour-only versus supply-inclusive

Contributions on contracts are generally assessed as a coefficient applied to gross work performed, not on the payroll lists filed. The logic is straightforward: the larger the labour share of the contract price, the higher the coefficient.

The precise coefficients and their scope are set in the organisation's revenue circulars and are periodically amended. The practical advice is to estimate the applicable coefficient before signing and price it into the bid. I have seen contractors model project margin precisely and omit the contribution coefficient entirely, losing the whole margin to it.

Why the materials split belongs in the text

If the agreement says only "performance of works for a lump sum of X" and is silent on who supplies materials, the branch will generally assume the less favourable position. If instead the contract states clearly that the contractor supplies the materials, and identifies their share of the price, the assessment basis changes fundamentally. The principle from the tax view of contracts applies here too: ambiguity always costs more than careful drafting.

Work performed at the contractor's own premises

Not every agreement attracts a coefficient. Where the contractor is a manufacturing or service business with a permanent workplace, its own workplace code and regular filings, and the contracted work was performed there, clearance can be issued on the basis of the lists filed and contributions paid for that period. The contractor must evidence this with the workplace code, the monthly lists, payment records, and their alignment with the contract period.

The route to clearance

1. Notify the branch covering the place of performance within the prescribed period and obtain the contract's workplace code.
2. File monthly lists for the project workforce under that code and pay the contributions.
3. Keep interim progress certificates, adjustments and addenda numbered and in order.
4. Obtain the completion or provisional handover certificate from the principal.
5. Apply for clearance with the contract, the final progress certificate and payment records.
6. Reconcile the assessed difference against your own calculation rather than simply paying it.
7. Object to the primary claims board within the statutory window if there is a discrepancy.
8. Once settled, deliver the certificate to the principal and pursue release of the retention and final instalment.

Objecting

After the demand notice is served, there is a statutory window to object; the file goes to the primary claims board and, if needed, the appeal board. In my experience, winning there requires no elaborate legal argument — it requires documentary coherence: a clearly scoped contract, progress certificates that match the payments, insurance filings consistent with the work period, and statutory books showing the same figures.

Parallel tax duties

A contracting agreement creates several obligations at once, and neglecting one damages the others: revenue recognition under contracting accounting, reporting the progress certificates in periodic filings, statutory withholding covered in withholding tax, and, on state work, the deductions and retentions discussed in government contracts. Running these four tracks independently guarantees reconciliation problems later.

Five clauses to include

1. Express allocation of workforce insurance and contribution payment to the contractor.
2. A clear split of materials, equipment and labour within the contract price.
3. An obligation on the contractor to file lists under that contract's workplace code.
4. Retention of five percent and the final instalment until clearance is delivered.
5. The principal's right to settle insurance debt directly from sums owed to the contractor on default.

Key takeaways

• Article 38 adds the principal to the liability rather than transferring it away.
• Contributions are usually assessed by coefficient on gross work, not on filed lists.
• Labour-only contracts carry a far higher coefficient than supply-inclusive ones.
• The materials split written into the contract directly changes the assessment.
• Never release the final instalment before the clearance certificate is in hand.