Your invoicing system shows ₹100,000. Your CRM shows ₹99,998. Your accountant's export shows ₹100,150. You have three numbers for one invoice, and none of them are wrong—they're just calculated at different points in a chain of systems that don't talk to each other cleanly. This is not a rare edge case. It happens at every handoff: CRM to invoicing, invoicing to accounting, accounting to the bank, and back again. By the time you notice, you've reconciled wrong, created duplicate adjustments, or filed a tax return with numbers that don't match your actual cash position. We traced seven places where invoice totals diverge, and built an audit checklist to catch the drift before your accountant does. The seven sync breaks Each break happens because systems calculate or round at different times, or because one system strips data that another needs. 1. Tax calculation: gross vs. net, and when it happens Your CRM captures the line item: ₹100,000. Your invoicing platform calculates tax on that line. But where does it calculate? Before discount? Some systems apply tax to the pre-discount subtotal, others after. If you issued a 10% discount, that's ₹10,000 difference in the tax base. Per-line or per-invoice? If you have multiple tax rates on one invoice (taxable + non-taxable items), systems that round per-line will differ from systems that round across the whole invoice. GST, SST, and e-Faktur rules vary by region here. When does the CRM see the final number? If the CRM records the gross total before tax is calculated, or if it doesn't fetch the final tax amount from the invoicing system, it holds a stale figure. The invoice is correct; the CRM is now wrong. An Indian vendor invoicing at ₹100,000 + 18% GST should show ₹118,000. If the CRM cached ₹100,000 and the invoicing system calculated ₹118,000, reconciliation fails. And if your invoicing platform doesn't push the final gross back to the CRM in real time, that gap widens every day. 2. Currency conversion: exchange rate timing and rounding You invoice a USD client ₹100,000 (about $1,200 at today's rate). Three systems, three questions: Which rate? The rate on invoice date? Payment date? Accounting close date? Your bank's rate or a mid-market rate? When does each system lock the rate? Your CRM might use today's rate. Your invoicing platform uses invoice-date rate. Your accounting system uses payment-date rate. By the time cash hits, you've reconciled to three different USD amounts. Rounding: where does it happen? If you convert line-by-line and then round, you get a different total than converting the subtotal and rounding once. Multiply this across 20 invoices in mixed currencies and your monthly reconciliation is off by ₹5,000. 3. Rounding: line-level vs. invoice-level A three-line invoice, each line ₹33,333.33: Line-level rounding: ₹33,333 + ₹33,333 + ₹33,333 = ₹99,999 Invoice-level rounding: ₹99,999.99 rounds to ₹100,000 Some systems apply rounding per line, others at invoice close. If your CRM records per-line rounding and your accounting system uses invoice-level rounding, they'll never match. This gap compounds with volume: 100 invoices at ₹1 per invoice drift is ₹100 unaccounted. 4. Late fees and interest: when they're added, and where An invoice is due in 30 days. On day 45, it's still unpaid. Your payment-tracking system adds a 2% late fee. Question: which system sees it? The invoicing system? Does it auto-generate a fee line item, or does someone manually add it? Your accounting system? Does it see the fee as a new line on the original invoice, or as a separate invoice? Your CRM? Does it update the contract value or the deal total? If the late fee is added in invoicing but not synced back to the CRM, your deal total is now wrong. If it's in accounting but not invoicing, your invoice PDF doesn't show it, but your tax report does. The invoice total across systems diverges without anyone making a deliberate change. 5. Partial payments and credit notes: which system records first A client pays ₹50,000 of a ₹100,000 invoice. Your bank records the deposit. Your accounting system creates a partial-payment entry. But when does the CRM know? Real-time sync? Most CRM-to-accounting integrations batch every 4–24 hours. Until the sync runs, the CRM shows the invoice as ₹100,000 unpaid, even though ₹50,000 is in the bank. Credit notes? If you issue a ₹10,000 credit note for a dispute, does it live as a separate invoice, a negative line on the original invoice, or a journal entry? Systems treat it differently. One might net it against the original; another might list them separately. Your accounts receivable aging report is now off. 6. Discounts and adjustments: recorded where, and when You grant a 5% discount mid-negotiation. Is it: A line item on the invoice? Then tax might apply to it (some systems tax negative lines). A separate credit note? Then it's a second document that must sync back. An invoice adjustment in accounting only? Then the invoice PDF your client