Employees who work from home on a structural and regular basis for a substantial part of their working time, may receive a flat-rate office allowance from their employer to cover all their office expenses.
The National Social Security Office (NSSO) informs us that this flat-rate office allowance is indexed.
The maximum flat-rate amount allowed by the NSSO as a reimbursement of costs and not subject to social security contributions is € 142.95/month from 1 September 2022.
The tax authorities also accept this amount as (non-taxable) reimbursement of expenses in accordance with the provisions of the Circular of 26 February 2021 on employers' compensations for homework.
Sources: Intermediate administrative guidelines for employers - NSSO – 2022/3, Circular 2021/C/20 on employers' compensations for homework, https://eservices.minfin.fgov.be/myminfin-web/pages/fisconet#!/document/9ab46041-d0bf-4438-b707-e7b847c4794c, 26 February 2021