How to calculate the real cost of your offices?

08/11/2019 - News

How to calculate the real cost of your offices?

In addition to the headline rent, the tenant of an office space generally takes over:

  • current expenditures of water, gas and electricity
  • maintenance expenditures and common repairs: heating appliances, counters, toilets, exterior shutters, interior and exterior painting, gardens, etc.
  • equipment expenditures of the condominium: elevator fees or maintenance staff costs for common areas
  • taxes related to the use of the office:

- Property Tax (P.I.). In Brussels, it represents on average +/- 41% of the indexed cadastral income.
- The tax on non-residential surfaces, or simply the “Brussels Regional Tax”. It amounts to € 8.7 per m² per year above the first 300 m² without exceeding 14% of the revalued cadastral income (order of July 23, 1992).
- In Brussels, each commune has developed its own office tax regulations. It amounts to 14.55 euros per m² per year, on average.
- Beyond a certain number of parking spaces per building, you may have to pay taxes on these excess parking, ranging from 250 to 450 euros/year per location, depending on the area.


Rents of business premises are expressed in €/m²/year, excluding taxes and charges. This formula does not include other costs: guarantee, insurance, lease registration, etc.


1.      Annual Indexation of Rents

Your contract will mention the conditions of this indexation: it usually happens annually, either on the contract signing date, or any date specified in the contract. Rent indexation follows the change of the official consumer price index (currently the health index).


2.      Security Deposit

The security deposit generally corresponds to 6 months of rent excluding taxes and prepaid expenses, but it can by convention relate to another amount, fixed by both parties.

2 formulas are possible: either on a blocked account, or in the form of a guarantee on first request of a banking institution (bank guarantee).


3.      Insurances

Either the tenant takes his responsibility (fire), or he contributes to the insurance concluded by the lessor with waiver of recourse by the insurer against the tenant.

The tenant is also required to insure the contents of the office.


4.      Lease Registration

The registration of the lease protects the lessee towards the new owner. Once registered, the lease is enforceable against all parties. This means that in case of sale or donation of the building, the new owner will have to respect the same registered lease as the former owner. On the other hand, he will be free to terminate the unregistered lease.

The registration of leases not assigned to the housing is paid and charged to the lessee. The registration fee is set at 0.2% of the tax base, i.e. the cumulative amounts of rent and charges imposed on the lessee for the duration of the lease.


5.      Others Costs to Consider

  • Moving expenses.
  • Internet subscription invoices.
  • Equipment maintenance (photocopiers, printers, coffee machines).
  • Development costs: decoration, refurbishment (which can be negotiated with the landlord), equipment or technical connection and furnishing.


As we can see, the real rental costs largely exceed the cost of rent. Hence the interest of working with experts, such as Trevi Corporate, who assist companies looking for offices to rent and adapt their proposals to your needs and financing capacity.