Compliance details last reviewed on 4 October 2026. Tax rules change often. This is general information, not tax or legal advice, so confirm specifics with your chartered accountant.
A purchase order sits in someone's inbox for four days. An invoice goes out without an IRN. A GST return is filed, and nobody compares it with the books until a notice arrives. None of these is a software failure. Each is a handoff that nobody owned.
This guide maps the six workflows every Indian B2B finance team runs: order to invoice, procure to pay, GST e-invoicing and e-way bills, TDS withholding, GST return reconciliation and month-end close.
For each one you get the trigger, the owner, the approval, the record an auditor will ask for, and the place it most often breaks. Near the end is a ten-minute checklist to score your own process.
What a B2B accounting workflow actually is
B2B accounting workflow: a repeatable chain with four parts. A trigger (something happens), an owner (one named person), an approval (someone with authority says yes) and a record (an entry nobody can quietly change). If any part is missing, the process runs on memory, and memory does not survive audits, resignations or month-end.
The 6 B2B accounting workflows
| Workflow | Trigger | Owner | Approval | Audit record | Common break |
|---|---|---|---|---|---|
| Order to invoice | Confirmed order or dispatch | Billing | Price and credit-limit exceptions | Invoice linked to order and payment | Invoice built from a spreadsheet copy |
| Procure to pay | Purchase need | Procurement and AP | PO by value; receipt before payment | PO, receipt, invoice, payment | Approval lost in email |
| E-invoice and e-way bill | Final B2B invoice or movement of goods | Billing; dispatch | GSTIN, HSN, place-of-supply check | IRN, e-way bill number | Reported late; edited after IRN |
| TDS withholding | Payment or credit to a vendor | AP and tax | Section and rate | Deduction, challan, return | Wrong section; late deposit |
| GST reconciliation | GSTR-2B generated | GST lead | Accept, reject or hold each invoice | Signed variance report | Matching against a stale 2B |
| Month-end close | Month end | Finance controller | Controller sign-off | Closed period, adjustments as new entries | Backdated edits |
1. Order to invoice
Trigger: a confirmed order or a dispatch. Owner: billing. Approval: a sales head signs off any price below list or any order above a customer's credit limit.
The invoice should carry a reference to the order, and every payment should be allocated against the invoice it settles. When it breaks, it breaks quietly. An invoice is typed from an old spreadsheet with last quarter's price.
A part-payment is allocated to the wrong invoice, so ageing is wrong and a collections call goes to the wrong customer. An invoice is finalised before GSTIN and tax details are checked, and the error surfaces later at e-invoicing.
Set one rule early: once an invoice is final, corrections go through a credit or debit note, never an edit.
2. Procure to pay
Trigger: a purchase need. Owner: procurement, then accounts payable. Approval: a PO approved by value, up the manager hierarchy, and a goods receipt before the supplier invoice is paid.
The record is the chain of PO, receipt, invoice and payment. The usual failure is an approval given on WhatsApp or email and never recorded, so nobody can show who authorised a spend.
Two Indian rules raise the stakes. First, if you owe a micro or small enterprise and pay later than the limit in Section 15 of the MSMED Act (the agreed period, up to 45 days, or 15 days with no written agreement), the expense is deductible only when paid.
That rule was Section 43B(h) of the 1961 Act and sits in Section 37 of the Income-tax Act, 2025.
Second, Rule 37 of the CGST Rules requires you to reverse input tax credit if you have not paid the supplier within 180 days of the invoice date. Both need an accurate payable ageing report. Confirm the current wording with your CA.
3. GST e-invoicing and e-way bills
Trigger: a final B2B invoice, or goods about to move. Owner: billing for the invoice, dispatch for the e-way bill. Approval: someone checks GSTIN, HSN and place of supply before generating the IRN.
E-invoicing applies to taxpayers whose aggregate turnover exceeded ₹5 crore in any financial year from 2017-18 onward (Notification 10/2023-Central Tax, in force since 1 August 2023).
The Invoice Registration Portal returns an Invoice Reference Number, a 64-character hash built from the supplier GSTIN, financial year, document type and document number. Taxpayers with turnover of ₹10 crore and above cannot report an e-invoice older than 30 days (GSTN advisory, 5 November 2024).
An e-way bill is generally needed when a consignment's value exceeds ₹50,000, and for regular cargo it is valid for one day per 200 km or part of it. Confirm current limits on the e-way bill portal.
The breaks: reporting after the 30-day window, dispatching before the e-way bill exists, and editing the invoice in your books after the IRN was issued, so the books and the portal disagree.
4. TDS withholding
Trigger: a payment or credit to a contractor, professional, landlord or other payee. Owner: accounts payable with tax. Approval: the section and rate are reviewed before deduction.
From 1 April 2026 the Income-tax Act, 2025 replaced the 1961 Act. TDS provisions now sit in Sections 392 and 393, and the Income Tax Department states that rates and thresholds were retained. Most teams, vendors and software still use the old 194C and 194J labels, which continue to apply to transactions before April 2026.
Deposit is due by the 7th of the following month (30 April for March). Quarterly statements are due on 31 July, 31 October, 31 January and 31 May; under the new rules, Form 140 replaces Form 26Q.
Late deposit attracts interest at 1.5% per month, and a late statement carries a fee of ₹200 per day, capped at the tax involved. Verify current forms and sections with your CA.
The breaks are predictable: the wrong section, threshold tracking kept per vendor in a spreadsheet, a missing PAN, and a deduction booked but not deposited.
5. GST return reconciliation
Trigger: GSTR-2B generation (the draft appears around the 14th of each month). Owner: the GST lead. Approval: an AP lead reviews each unmatched supplier invoice.
The Invoice Management System (IMS), live since October 2024, lets you act on each supplier record before GSTR-2B is final. Accepted records flow into ITC available, and into GSTR-3B. Rejected records do not auto-populate. Pending records stay out of both GSTR-2B and GSTR-3B.
A record with no action is deemed accepted when GSTR-2B is generated. Credit is time-barred after 30 November following the financial year end (Section 16(4)). The portal also stopped accepting returns more than three years past their due date from 1 December 2025.
Reconcile in two directions: purchases against GSTR-2B for credit, and sales against GSTR-1 and GSTR-3B for liability.
The breaks: matching against an old GSTR-2B, leaving records on "no action", and supplier invoice numbers that differ by a dash or a leading zero. The output of this workflow is a variance report with a named person's sign-off.
6. Month-end close
Trigger: the month ends, ahead of the GST due dates. Owner: the finance controller. Approval: the controller signs a checklist: invoices final, payments allocated, TDS computed, GST reconciled.
The record is a closed period. A late correction becomes a new, dated entry in the open period, never an edit to the closed one. It breaks when invoices are backdated into a closed month, when reconciliation happens after the return is filed, and when the "close" is a spreadsheet that only one person understands.
Where spreadsheets and email create risk
Spreadsheets and inboxes are fine for drafting and poor as the system of record.
- Edited cells. A changed amount leaves no trace of the old one or who changed it.
- Lost approvals. An approval living in a chat thread cannot be produced during an audit.
- No sequence. Without enforced order, the e-invoice is generated before the check, or the payment is made before the receipt.
What an audit-ready ledger looks like
Three properties matter. Amounts are stored as whole integers in the smallest currency unit (paise for rupees), so rounding never drifts between invoice and ledger. Entries are never edited. A correction is a new row that references the one it fixes. And every sensitive action, an approval or the reveal of masked personal data, leaves its own record.
Indian companies have a statutory reason to care. The Companies (Accounts) Rules, 2014 require accounting software used from financial years starting on or after 1 April 2023 to record an audit trail of each transaction, with an edit log that cannot be disabled. Ask your auditor how this applies to you.
Which workflow to automate first
Rank by what happens when it fails, then by effort. Upstream workflows feed downstream ones, so fix the front of the chain first.
| Priority | Workflow | Risk if it fails | Effort to fix |
|---|---|---|---|
| 1 | E-invoicing and e-way bills | High: statutory, visible to customers | Low to medium |
| 2 | GST reconciliation | High: lost credit, notices | Medium |
| 3 | TDS withholding | High: interest and fees | Medium |
| 4 | Order to invoice | Medium: errors flow into everything | Low |
| 5 | Procure to pay | Medium: control and cash | Higher: needs approvals and receipts |
| 6 | Month-end close | Medium: follows from the rest | Low once 1 to 5 are clean |
Score your process in about 10 minutes
Answer yes or no for each. One point per yes.
- Every invoice is raised from a record linked to an order, not from a copied file.
- Every payment is allocated against a specific invoice.
- Corrections to final invoices are made by credit or debit note, never by edit.
- Each e-invoice is generated, and its IRN stored, before the invoice is sent.
- You can list every e-way bill raised last month and the invoice behind it.
- TDS section and rate are chosen from one maintained source, not by memory.
- TDS is deposited by the 7th and the challan is attached to the deduction.
- GSTR-2B is reconciled before GSTR-3B, with a named reviewer's sign-off.
- Every PO approval is recorded with who approved and when.
- Closed periods cannot be edited without a dated, referenced adjustment.
0 to 4: fix e-invoicing, TDS and reconciliation first. 5 to 8: you have the basics; automate the failing handoffs. 9 or 10: test the controls with a sample audit request.
Where OpsGrids Finance fits
OpsGrids Finance covers invoices, payments and allocations against them, GST registration, returns and a return diff, and TDS withholding, on a full ledger. The e-invoicing (IRN), e-way bill and IMS workflows are e-invoice-ready but run against a simulated government portal today; until the live connection ships, use the official portals or your GST Suvidha Provider.
Invoices are append-only: a correction is a new row. Events such as an invoice being finalised or an approval being decided can be routed to people on WhatsApp or email through notification rules.
Two limits. Routing purchase-order approvals up the reporting line, and matching a goods receipt to the supplier invoice, are designed but not live. Finance reconciles against its own purchase book today. And no software guarantees compliance: your data, portal availability and your CA's judgement still decide the outcome.
FAQ
How do I automate B2B invoicing in India? Start with the order-to-invoice link, then add e-invoicing. Keep one customer and item master, raise invoices from orders, generate the IRN before sending, and allocate each payment to an invoice.
What is an IRN and how is it generated? The Invoice Reference Number is a 64-character hash created by the Invoice Registration Portal from your GSTIN, the financial year, the document type and the document number.
Is e-invoicing mandatory for my business? Generally if your aggregate turnover exceeded ₹5 crore in any financial year since 2017-18, subject to exemptions. Check the notification and your CA.
What are the steps in GSTR-2B reconciliation? Wait for GSTR-2B, match it against your purchase register, act on each IMS record, chase suppliers for gaps, and record a sign-off before filing GSTR-3B.
Did TDS rules change in 2026? The Income-tax Act, 2025 took effect on 1 April 2026. Sections were consolidated and some forms renumbered, but the department states that rates and thresholds were retained.
See these workflows running in one platform
Want to see how this maps to your own process? Talk to our team for a walkthrough.
Sources (checked 4 October 2026)
- GSTN advisory on the 30-day e-invoice reporting limit, 5 November 2024 (einvoice.gst.gov.in)
- IRN specification, Invoice Registration Portal (einvoice6.gst.gov.in/content/irn-2/)
- Notification 10/2023-Central Tax, 10 May 2023 (gstcouncil.gov.in/node/4365)
- GSTN FAQs and advisory on the Invoice Management System (tutorial.gst.gov.in)
- GST Council Newsletter, Issue 79, October 2025 (gstcouncil.gov.in)
- Income Tax Department: TDS compliance and tax-payments FAQ pages (incometax.gov.in)
- PIB: Income-tax Act, 2025 comes into force, 1 April 2026 (pib.gov.in)