GST on SOR Items — How to Apply in Tender BoQ + GFR Treatment

One of the most-mishandled topics in Indian tender preparation is GST on SOR-based BoQ. Engineers cite SOR rates without GST, contractors quote with-GST without saying so, finance flags the discrepancy three months in, and project margins evaporate. This guide is the clean answer: SOR rates are GST-exclusive, GST is added separately at the BoQ summary level, and there are well-defined rules for how the contractor recovers GST on inputs.

If you tender against CPWD DSR, MoRTH SOR, or any state PWD SOR — read this once, never lose money on it again.

The Core Rule

Every SOR rate published in India is GST-exclusive. This applies uniformly to CPWD DSR, MoRTH SOR, MES SOR, all state PWD SORs, and ULB SORs.

The reasoning is procedural. SORs are derived from material rates, labour rates, and a CP&OH percentage — none of which are GST-inclusive at the input level (GST flows differently for materials vs labour vs services). Adding GST inside the SOR rate would force re-derivation every time the GST regime changes.

So the SOR-based BoQ has two layers:

1. Item line — quantity × SOR rate (GST-exclusive). This produces a sub-total.
2. GST line — typically @ 18% of the sub-total, added at the bottom of the BoQ.

What GST Rate Applies to Civil Works?

For most CPWD, state PWD, and private civil tenders, you'll apply 18% GST on the GST-exclusive BoQ subtotal. Verify the applicable rate by checking the tender entity's GST notification at NIT (Notice Inviting Tender).

BoQ Format — Where GST Goes

A standard CPWD-format BoQ summary has the following structure:

The GST line goes after the BoQ subtotal and before any contingency or escalation lines. Some tender formats require a separate GST column per item; for CPWD-format that's discouraged because it adds clutter without changing the math.

Reverse Charge Mechanism (RCM) — When the Contractor Pays GST on Behalf of the Client

RCM under GST applies when goods/services are supplied by an unregistered supplier to a registered recipient. In civil works:

• Material supply by unregistered local vendors — typical for sand, brick, aggregate sourced from village suppliers. Contractor pays RCM @ applicable rate.
• Cartage / freight by unorganized transporters — RCM @ 5% (without ITC) or 12% (with ITC).
• Security services from unregistered providers — RCM applies.
• Labour from unregistered contractors — RCM applies if labour is supplied as a "service".

RCM is the contractor's compliance burden, not yours as the tender issuer. But it affects their margin — savvy contractors load RCM-related risk into their bid above the SOR-based subtotal.

ITC (Input Tax Credit) — How the Contractor Recovers GST

The contractor pays GST on inputs (materials, services) and charges GST on output (the works contract). They claim Input Tax Credit on the difference:

Key implication: materials priced into SOR rates are computed pre-GST. The contractor pays GST on inputs (which they fully recover via ITC) and charges GST on output. The SOR rate captures the pre-GST cost; the BoQ GST line captures the output charge.

Common Errors

1. Bidding GST-Inclusive on a GST-Exclusive Tender

Most disastrous mistake. SOR-based tender expects bids in GST-exclusive rupees. A contractor who quotes "all-inclusive" loses 18% on the bid evaluation. Always verify the NIT clause: "Quoted rates shall be exclusive of GST. GST shall be paid extra at applicable rates."

2. Treating GST as Negotiable

GST is statutory — not part of the commercial negotiation. The contractor cannot offer "discount on GST" — that's tax evasion. Discounts apply to the rate; GST then applies on the discounted rate.

3. Forgetting Cess and Surcharge

For specific projects (e.g., GST Compensation Cess on certain inputs), the cess applies on top of GST. Most building works contracts don't see cess directly because it's an input issue handled by the contractor.

4. Misclassifying Composite vs Pure Services

If your contractor's scope is labour-only (you supply materials), it's a "pure service" — different GST rate (often 18% on labour, with no underlying material GST flow-through). If contractor supplies both materials and labour, it's "works contract" — 18% on the composite. Get the classification right at NIT.

5. Cost Index + GST Sequencing

For tenders that apply a Cost Index (e.g., MoRTH revisions, central body revisions), the sequence is: SOR rate × Cost Index = adjusted base rate, then GST @ 18% on that. Some tenders apply GST first, then Cost Index — wrong sequence loses 1–2% to rounding.

GFR (General Financial Rules) Treatment

GFR 2017 governs central government procurement (CPWD and ministries). On GST in tenders:

• Rule 152 — competitive tendering basis is GST-exclusive rate; GST shown separately
• Rule 159 + 160 — bid evaluation comparison must be on GST-exclusive figures (rate only)
• Rule 173 — variations during execution use the original SOR rate × variation quantity, GST applied on the resulting amount

State financial codes mirror GFR with minor variations. Maharashtra's PWD Manual, Karnataka's KTPP Act, and similar publications follow the same GST-exclusive-rate-then-GST principle.

Special Cases

Government Department as Service Recipient

When CPWD or PWD is the service recipient (i.e., the construction is for government use), the supplier (contractor) charges GST. The department deducts GST TDS at 2% from the payment under section 51 of CGST Act. The contractor then files a return claiming this 2% as paid to government.

Affordable Housing under PMAY-U

Different GST treatment: 1% (no ITC) for affordable housing or 5% (with ITC). The contractor cannot mix-and-match — all units in a project follow one regime. Affects tender pricing materially: 5% with ITC is usually 4–6% cheaper than 18% with ITC for the same scope.

SEZ Projects

Supply to SEZ developer is "zero-rated" — contractor pays no GST, claims refund. Tender rate negotiation is at GST-exclusive base; the GST line in BoQ is zero or shown as zero-rated.

Inter-state Project Sites

If supplier and client are in different states, IGST applies (instead of CGST + SGST). Same 18% total — only the routing differs. No impact on BoQ math.

Worked Example — Pre-GST and Post-GST BoQ

A 2,000 sqft G+1 residential building tender at DSR 2023 rates:

The contractor signs against ₹46,02,000. They invoice the client in stages with GST broken out (typically running bills). The client pays the full invoice value but deducts 2% GST TDS where applicable (CPWD/govt) and reports it.

FAQ

Are CPWD DSR rates inclusive of GST?

No. DSR rates are GST-exclusive. GST is added separately at the BoQ summary level. This applies to all CPWD SOR-based tenders.

What GST rate applies to my construction tender?

For most civil works contracts: 18%. For PMAY-U affordable housing: 1% (no ITC) or 5% (with ITC). For specified government services: 12%. Always verify the applicable rate from the tender NIT.

Can the contractor charge me GST on the SOR rate directly?

Yes — that's exactly how it works. The contractor charges (SOR rate × quantity) + 18% GST on the total. The SOR rate is the labour-and-material cost basis; GST is the statutory output tax.

Does GST apply to labour-only contracts?

Yes. Labour-only contracts are typically "pure services" — 18% GST applies. Some specific service categories (skilled labour to govt entities, manpower supply) have specific notifications; check the GST council notifications for your scope.

What happens if my contractor is unregistered (composition scheme)?

Composition scheme contractors charge 5% (instead of 18%) but cannot pass on ITC. For a registered client (companies, govt), this typically means higher net cost because you can't claim ITC against the 5%. Most large tenders specify "Bidder must be regular GST-registered" to avoid this.

Do I include GST in tender comparison?

No. Per GFR Rule 159, bid comparison is on GST-exclusive rates. Different bidders may have different ITC positions; comparing on GST-exclusive isolates the rate competitiveness.

How do I handle GST on retention money?

GST is paid on the gross invoice value, not on the net (post-retention). Retention money is held against contract performance, not against tax liability. When retention is released (typically after defect liability period), no further GST is charged on the released amount.

What if my SOR is from 2018 (pre-revision) and current GST rate is different?

SOR rates are inflation-adjusted via Cost Index multipliers. GST is applied on the (SOR × Cost Index) result at the GST rate prevailing at the date of supply, regardless of when the SOR was published. Don't try to backdate GST to the SOR's publication year.

Related

DSR 2023 Complete Guide · SOR for Tender Preparation · Rate Analysis 10 Examples · SOR Editions Tracker