Specific measures against social fraud

A contractor may have social debts with the NSSO or tax debts with the FPS Finance. If so, you as the client are not allowed to pay the entire invoice to the contractor. In such cases, you have to retain a part of it and pass it on to the NSSO and/or FPS Finance.

What is meant by ‘Withholding obligation’?

Clients, contractors and subcontractors who have activities carried out as described below are required to check whether their (sub)contractors have social or fiscal debts. If this is the case, they have to withhold a certain percentage of the invoice amount and pass it on to the NSSO (for social debts) or the FPS Finances (for tax debts).

Which activities are affected by the withholding obligation?

The regulations on the withholding obligation on invoices cover:

• Works on immovable property (art.30bis of the law of 27 June 1969), with the exception of certain activities of agriculture, horticulture and forestry which are explicitly excluded from the area of application.
• Supply of ready-mixed concrete as referred to in article 1, a, fifth paragraph, twenty-eighth indent of the Royal Decree of 4 March 1975 on the establishment and determination of the name and competence of the Joint Committee for the Construction Industry and fixing the number of its members.
• Works falling under the Joint Committee for guarding and/or surveillance services (art. 30ter of the Act of 27 June 1969 - Royal Decree of 17 July 2013).
• Works in the meat sector (art. 30ter of the Law of 27 June 1969 - Royal Decree of 22 October 2013).

Social debts with the NSSO

If the contractor has social debts, the client has to deduct 35% of the invoice amount and transfer it to the National Social Security Office ( to account number BE76 6790 0001 9295 with BIC: PCHQBEBB).

Fiscal debts with the FPS FinanceIf the contractor has tax debts, the client hast to deduct 15% of the invoice amount and pay it on to the FPS Finance (to account number BE33 6792 0023 2046 with BIC: PCHQBEBB).

Consult the ‘Manual Withholding obligation’ for a step-by-step guide on how to proceed in detail.

You can use the Declaration of works to notify the NSSO and relevant inspection services of work being carried out on properties.

Which works do you have to declare?

For work on properties and the supply of fresh concrete (30bis), you have to submit the following declarations:

• - any ‘client – contractor contract’ of 5,000 euros or more (excluding VAT) with at least 1 subcontractor;
• - any ‘client – contractor contract’ of 30,000 euros or more (excluding VAT) with or without subcontractors;
• - work that is hazardous due to the presence of asbestos.

Work covered by the Joint Commission for Security and Locking Services and certain activities in the meat sector also have to be declared (30ter).

When should the declaration be submitted?

The declaration has to be submitted before work starts.

If it concerns works on a temporary or mobile construction site or asbestos removal works, the declaration has to be submitted at least 15 calendar days before the start of the works. You can access the online service Declaration of works on the page Declaration of works on the Social Security portal (in French). Select the button that is relevant to you in the column on the right.

Consult the ‘Manual Declaration of works’ for a step-by-step guide on how to proceed in detail.

‘CheckInAtWork' is an online platform provided by the NSSO to ensure that employers register their workforce correctly.

What is CheckInAtWork?

CheckinAtWork is the online service for the attendance registration concerning the delivery of ready-mixed concrete, activities falling under the meat sector and for works on immovable property, with the exception of certain agricultural, horticultural and forestry activities that are explicitly excluded from the area of application. It concerns the registration of:

• anyone who carries out works on immovable property (in french) at a workplace with a total cost equal to or exceeding 800,000 euros;
• anyone who carries out activities related to meat preparations or meat products and the slaughter or cutting of hoofed animals, poultry and rabbits in establishments subject to the approval (approvals, authorisations and prior registrations) of the Federal Agency for the Safety of the Food Chain (FASFC).

Via CheckInAtWork, employers and contractors register the presence of their own employees, their subcontractors and their independent subcontractors. Employees and independent subcontractors can also register themselves on their own in the system.

Registration must be made daily and before the person carrying out the works starts work.

Workplaces covered by the compulsory attendance registration via CheckInAtWork must be declared in the Declaration of Works (in french).

Consult the ‘Manual Checkinatwork’ for a step-by-step guide on how to proceed in detail.

Social Security Contact Centre

Telephone: +32 (0)2 511 51 51

You can also get in touch via our Contact page.