Why RA billing goes wrong
On most Indian construction contracts you are paid in instalments called running account (RA) bills. Each one claims the work done since the last bill, at the rates in the contract BOQ. On paper that sounds simple. In practice it is where a contractor’s cash flow is won or lost.
The usual problems are familiar to any QS or project manager:
- The bill lives in an Excel workbook that only one person understands, with formulas copied from the last project.
- This period’s quantity is typed in directly, so a mistake in bill 4 quietly carries into bills 5, 6 and 7.
- Quantities creep past the BOQ because extra work was done on site but never approved as a variation.
- Retention, advance recovery and liquidated damages are worked out by hand, and nobody is sure how much retention is held across all projects.
- The client certifies less than you claimed, and the invoice still goes out at the claimed figure.
Good RA bill software exists to remove these failure points, not to make a prettier spreadsheet.
How RA billing works in India
The process is broadly the same whether your client is a government department, a PSU, a developer or a private owner:
- Measurement. Work done is measured against the items of the contract BOQ, usually following the method of measurement named in the contract (for civil work this is often IS 1200).
- Cumulative quantities. Each bill records the quantity executed to date. The quantity for this bill is the cumulative figure minus everything billed before.
- Claim. The bill is valued at the contract rates and submitted to the client’s engineer or consultant.
- Certification. The client checks the measurement and certifies a quantity, which may be lower than the claim.
- Deductions. From the certified gross value, the client deducts retention money, recovery of any mobilisation advance, liquidated damages where they apply, and statutory deductions such as income-tax TDS and, for government clients, GST TDS.
- Invoice and payment. A GST tax invoice is raised for the certified work and the net amount is paid.
Extra or changed work is handled through a change order (also called a variation). Until it is approved, the extra quantity has no contract rate and should not be billed.
For a fuller explanation of retention and advances, read RA bills, retention and advances: getting construction billing right.
What to look for in RA bill software
When you compare tools, check for these:
- Measurement against the contract BOQ, not a free-typed list of items.
- Cumulative entry, so corrections carry forward automatically.
- An over-billing check against BOQ quantities, with a clear route for approved variations.
- Separate claimed and certified figures, with the invoice driven by certification.
- Contract terms captured once at award — retention, advance and LD — and applied to every bill.
- A retention register across projects, with partial and full release.
- GST invoicing from the certified bill, with place of supply and TDS handled properly.
- A link to cost, so certified revenue can be compared with what the project has actually spent.
How Zaptiz Construction handles RA bills
Zaptiz Construction keeps the whole chain — BOQ, award, measurement, certification, deductions, invoice and payment — on one project record.
Terms set at award
When a quotation becomes a contract, the award records retention, advances, the defect liability period and LD terms. RA bills apply those terms; nobody re-keys percentages each month.
Cumulative measurement with an over-billing guard
For each BOQ item worked on, the QS enters the total quantity executed to date. Zaptiz subtracts what has already been billed and values this bill at the contract rate. If a cumulative quantity would exceed what the contract BOQ allows, the over-billing guard warns you before the bill goes out. Genuine extra work is priced as a change order, submitted to the client and, once approved, added to the contract.
Certification drives the money
When the client certifies, you record the certified quantities. Those figures — not the claim — drive the invoice, the retention held and the revenue shown in project financials, where revenue is recognised at certification against budget and cost.
Deductions and a retention register
Advance recovery, LDs and retention are applied from the award terms. Retention held on each project is tracked in a retention register, with partial or full release when it falls due.
GST invoice and payment
The tax invoice is created from the certified bill. Place of supply is the site, which determines CGST and SGST or IGST, and TDS fields are included. You can send the bill and invoice by email or WhatsApp, add a pay link through your own Razorpay or Stripe account, and allocate payments against invoices in the company-wide payments register.
An AI agent that drafts, not decides
The RA Bill Drafting agent prepares the next bill’s quantities with the over-billing check applied. It is a draft: the QS reviews each quantity against measurement records and site daily progress reports before anything is submitted. See how Zaptiz AI works.
What it does not do
Drawing takeoff in Zaptiz Construction is currently a PDF viewer with calibrated scale and a ruler; area, count and quantity takeoff is coming soon, so measurement comes from your own records. Price escalation can be flagged but is not calculated. Credit notes and e-invoicing are not available.
The step-by-step version is in the guide Running RA bills in Zaptiz Construction.
Get started
If your RA bills still live in workbooks, start with one live project: import its BOQ from Excel, record the award terms and run the next bill in Zaptiz alongside your usual sheet. Book a demo to walk through it with your own BOQ, or see pricing to request a quote.