What is a SAC code?
SAC codes classify services for GST, the way HSN classifies goods. How they are structured and where they are used.
SAC (Services Accounting Code) classifies services for GST, in the same role
HSN plays for goods. Every SAC begins with 99, which is what
distinguishes a service code from a goods code at a glance.
Structure
99 identifies it as a service. The following digits narrow it: chapter, then group,
then the specific service. So 998313 — management consulting — reads as services
(99), then professional/technical (83), then the specific consulting category.
Where SAC appears
- On tax invoices for services
- In GST returns
- In contracts and purchase orders, where the parties want the tax treatment agreed rather than assumed
Mixed and composite supply
This is where classification gets genuinely hard. A contract covering both goods and services — supply and installation, for example — may be a composite supply, taxed at the rate of the principal supply, or a mixed supply, taxed at the highest applicable rate. Which it is depends on whether the elements are naturally bundled.
Getting that wrong changes the rate on the whole contract, not just one line.
What people get wrong
Assuming every service is 18%. It is the most common rate, not the only one.
Treating supply-and-install as two separate transactions when it is one composite supply, or the reverse.
Not stating SAC in the contract. If the tax treatment is disputed later, the absence of an agreed code makes it the supplier's problem.
On Bidancer
Service signals capture scope and delivery terms in a structured form, so the commercial shape of the service is explicit before an enquiry is raised.