There is one question that quietly decides how complicated your GST life is going to be, and most studios never actually stop to answer it, which is: are you selling design, or are you selling a finished space? Because "interior designer" covers two very different businesses under one word, the studio that hands over drawings and a specification and walks away, and the studio that takes the whole job to handover with contractors, furniture and finishes on its own bill, and GST treats those two studios differently. If your invoices, your codes and your tax feel messier than a friend's who does similar work, this is very often the reason, and this post is here to make the distinction clear so you stop mixing the two by accident.
Let me be honest up front, this is the one area where I will tell you to loop in your CA on the edge cases, because contract structure matters. But you should walk into that conversation knowing the shape of it, so here it is.
Two businesses hiding inside one word
Consultancy is clean. You provide a service, design, drawings, specification, maybe site supervision, and you bill a professional fee. One supply, one rate, one line of thinking. Execution is a different beast, because now you are also supplying goods and often labour, a modular kitchen, wardrobes, tiles, lighting, false ceilings, paint, and the tax has to account for the goods separately from the service, or treat the whole thing as a single bundled supply depending on how you have written the contract.
The practical test I use is simple, does the client pay you for the sofa, or does the client pay the vendor and pay you a fee for choosing it? If the money for the goods flows through your studio, you are in execution, and your GST just got more involved. If it does not, you are a consultant, and your GST stays simple. Get honest about which one you are, project by project, because a studio can genuinely be a consultant on one job and an executor on the next.
What changes on the tax, side by side
Here is the comparison laid out the way I wish someone had shown me early.
| Dimension | Pure consultancy | Execution / turnkey |
|---|---|---|
| What you supply | A service only | Service plus goods, often plus labour |
| Classification | Service, under a SAC code | Supply of goods on HSN, or a works contract treated as service |
| GST rate | 18% on the fee | 18% on the service line, each good at its own HSN rate |
| Invoice shape | One clean service line | Multiple lines, service and goods split, or one works-contract line |
| Input tax credit | Small, on your own inputs | Large, on all the goods you buy to supply |
| Documentation load | Light | Heavy, every vendor bill matters |
Notice the input tax credit row, because it flips the whole feeling of the two models. A consultant collects a lot of output tax and has little to offset, so the net GST feels high. An executor collects output tax but also pays a mountain of input tax on the goods, so the credit is large and the net is smaller, which is exactly the mechanic I walked through in how much GST designers actually pay. Same 18% headline, completely different cash reality.
The works-contract wrinkle
Here is where people trip. When design and execution are bundled into a single turnkey price for a specific property, "do my whole flat for one number", that can qualify as a works contract, which under GST is treated as a supply of service, not goods, even though tonnes of material change hands. That means the whole thing may sit at 18% as a service, rather than you splitting out each tile and light at its own rate.
Whether your job is a works contract, a composite supply, or just a service with some goods attached depends entirely on how the contract is written and how the money flows, and the definitions genuinely matter here, so this is the one place I point studios to CBIC-GST for the actual wording rather than a summary, and then to a CA to confirm the treatment for your specific contract. Guessing this one is expensive in both directions, you either overcharge the client or understate your liability.
Getting the codes right for each model
The codes are where the two models become visible on paper. Consultancy rides on a service code, the SAC, while every good you supply in execution rides on its own HSN. Mix them up and your invoice contradicts itself, which is the fastest way to get a bill bounced by a sharp client accountant. I put the specific numbers in the guide to HSN and SAC codes for interior design, and you can sanity-check any code against a public HSN and SAC lookup before it goes on a document.
For a consultant, this is a two-minute job, one SAC, one rate. For an executor, it is a discipline, because a turnkey job might touch fifteen HSN codes across furniture, sanitaryware, electricals and finishes, and every one of them has to be right for your client to claim credit cleanly and for your own return to reconcile.
That gap in the bars is the whole point. Consultancy is a short invoice. Execution is a long one, and a long invoice done by hand in Excel at 11pm is where wrong codes and broken number series are born.
Why the model decides your tooling
Here is the operator truth. A consultant can almost survive on spreadsheets, because the invoice is short and the credit is small. An executor cannot, because you are tracking dozens of vendor bills for input credit, splitting goods and services on every invoice, and often billing in stages against milestones, which brings its own GST timing questions that I covered in invoicing milestones under GST. The volume of documents in execution is simply too high for scattered tools to hold without leaking credit or breaking the invoice series.
This is the practical case for one connected system, and I mean it specifically, not as a slogan. When your room-by-room specs, the goods you are supplying, the approved quote and the final invoice all live together, the model you are in, consultancy or execution, is expressed correctly and automatically, the SAC and HSN carry through, and the vendor bills that back your credit are captured as you buy, not reconstructed at filing. I made the full argument for that in why one connected system beats five disconnected tools, and the same logic runs right through to your income tax, because a clean GST trail is also a clean records trail when you file on the Income Tax portal. If you are still weighing whether the ground-up GST basics apply to you at all, the plain-English GST guide for interior designers is the place to start.
Key takeaways
- Decide per project whether you are a consultant or an executor, the money flow tells you
- Consultancy is one service line at 18%, execution splits goods on HSN or bills a works contract
- Execution carries big input tax credit, so the net GST feels lighter than the headline
- Works-contract treatment depends on contract structure, so confirm the edge cases with your CA
Frequently asked questions
Is interior design consultancy taxed differently from execution under GST?
The design service is 18% in both, but pure consultancy is a single service supply, while execution adds goods on their own HSN codes, or may be treated as a works contract, which changes the invoice structure and the input credit.
What is a works contract for an interior studio?
A bundled, turnkey supply of design and execution for a specific property under one price. Under GST it is generally treated as a supply of service, so it can sit at 18% rather than being split good by good.
Do I charge GST on the furniture I supply to a client?
Yes, if the money for the goods flows through your studio, each item carries its own HSN code and GST rate, unless the whole job is structured and treated as a works contract.
How do I know which model my project is?
Follow the money. If the client pays you for the goods, you are executing. If the client pays vendors directly and pays you only a fee, you are consulting.
The cleanest way to think about it is this, consultancy and execution are not two labels for the same job, they are two different tax positions, and the trouble starts the day you invoice one as if it were the other. Know which one you are on each project, code it correctly, and GST stops being a monthly mystery.
If you want to see how the same workspace expresses both models cleanly, from a consultant's short invoice to an executor's long one, there is a live demo at demo.designa.work, and the founding offer is one flat price for the whole studio, billed in rupees with unlimited free client logins, at go.designa.work.