KBO.party offers the monthly KBO csv export as a REST service.
Free in beta
Lookup company by VAT id
kbo.party/api/v1/enterprise/362475538
kbo.party/api/v1/enterprise/759806938
kbo.party/api/v1/enterprise/923016762
Lookup establishment by VAT id
kbo.party/api/v1/establishment/2104957507
kbo.party/api/v1/establishment/2077711393
kbo.party/api/v1/establishment/2073554647