You send an invoice for ₹1,00,000. Your CRM shows it. Your accounting system shows ₹99,847 in the GL. Finance says reconcile. Two hours later you've found ₹153 in rounding and a duplicate tax line, but ₹2,000 still doesn't match. Invoice-to-GL divergence is not random. It follows nine predictable paths: tax misallocation, currency rounding, discount application, entity posting splits, duplicate entries, timing differences, manual GL adjustments, withholding offsets, and multi-leg transactions that fragment across lines. This guide traces each break. By the end you'll have a checklist to audit ₹1,00,000 in 90 minutes and spot the pattern before month-end scramble hits. 1. Tax is allocated to the wrong GL account Most invoicing platforms post tax to a single 'Tax Payable' GL code. Your actual liability lives across three accounts: GST/SST collected: liability (balance sheet) GST/SST paid on purchases: receivable (reduces liability) Tax expense: P&L (only for non-recoverable tax) An invoice for ₹1,00,000 + ₹18,000 GST posts as: Debit: Accounts Receivable ₹1,18,000 Credit: Revenue ₹1,00,000 Credit: Tax Payable ₹18,000 But your GL structure expects: Credit: Tax Collected (liability sub-account) With a tag for input credits you can recover If your invoicing tool doesn't map tax to the correct GL codes—or doesn't split recoverable from non-recoverable—your tax line reconciles to the wrong number. In India, Malaysia, and Singapore, auditors flag this immediately. Audit step: Pull a sample invoice. Check the GL entry. Verify tax posts to the liability account you've designated. If it's a catch-all 'Tax' code, remap it before your next invoice. 2. Multi-currency invoices round at three different stages You invoice a US client ₹1,00,000 in USD. The rate is 83.47 INR/USD on invoice date, but GL posting uses yesterday's rate (83.42). Payment arrives three weeks later at 83.61. Your invoice posts at: ₹1,00,000 ÷ 83.47 = $1,198.00 USD GL posts at: $1,198.00 × 83.42 = ₹99,909.16 INR Payment arrives at: $1,198.00 × 83.61 = ₹1,00,163.78 INR Now you have ₹254.62 floating in an FX Gain/Loss line that didn't exist on the original invoice. Many invoicing platforms don't post the FX variance to GL at all. They let it sit in a 'pending' state. If your system doesn't handle realized vs. unrealized FX gains, this line will diverge every month. Audit step: For every multi-currency invoice, verify your system posts: Invoice amount in home currency at invoice-date rate Accounts Receivable adjustment when payment rate differs FX Gain/Loss line to a dedicated GL account If your invoicing tool doesn't offer this, the variance will compound monthly. 3. Discounts post to revenue instead of a contra account You invoice ₹1,00,000 and apply a 10% early-pay discount (₹10,000). Your invoicing tool posts: Debit: AR ₹90,000 Credit: Revenue ₹90,000 But accounting standard practice posts: Debit: AR ₹90,000 Credit: Revenue ₹1,00,000 Debit: Discount Given ₹10,000 (contra-revenue) Why? Your auditor needs to see gross revenue. Discounts tell a story: seasonal pressure, cash shortage, customer retention risk. Burying discount in revenue hides signal. When you reconcile, you're comparing ₹90,000 in your invoice tool against ₹1,00,000 in your GL because the GL system is right and the invoice tool is wrong. Audit step: Check your invoicing platform's discount settings. Does it have a dedicated 'Discount Given' GL account? If not, you'll need a manual journal entry each month, which is error-prone and auditable risk. 4. Multi-entity invoices split to two GL books at different times You have two legal entities: Orin India Pvt Ltd and Orin Singapore Pte Ltd. A customer pays one entity but the invoice was issued by the other (common in holding company structures). Your invoicing system posts to Entity A's GL immediately. Payment lands in Entity B's bank account three days later, which auto-posts to Entity B's GL. Now reconciliation is broken because AR and Cash are in different books. Most invoicing platforms don't handle inter-company transactions. They post each entity separately without a linking journal. So you reconcile Entity A alone (AR outstanding) and Entity B alone (mystery cash), and both show 'unreconciled.' Audit step: If you operate multiple legal entities, verify your invoicing platform supports inter-company transactions with automatic offsetting GL entries. If not, you'll reconcile each entity in silos and lose the inter-company audit trail. 5. Duplicate GL entries from retry logic or webhook failures Your invoicing system tries to post to GL via API. The network hiccups. The system retries and succeeds. But the first request also succeeded—silently—and now you have two identical GL entries. ₹1,00,000 invoice posts twice: Debit: AR ₹1,00,000 (entry 1) Debit: AR ₹1,00,000 (entry 2—duplicate) Credit: Revenue ₹2,00,000 Your reconciliation now shows ₹2,00,000 in revenue against ₹1,00,000 invoiced. If you don't catch this in the first week, it snowb