The Complete Guide to Indian Business Data Migration

Every Indian business going through an ERP implementation faces the same decision: what to bring across from the old system, and what to leave behind. Get this wrong and you'll spend months reconciling bad data. Get it right and your new system starts with a clean, reliable foundation.

The Three Categories of Migration Data

Must migrate: Master data (customer, vendor, product/service catalog, chart of accounts), opening balances (all outstanding payables and receivables as of migration date, bank balances, inventory quantities and values), and active contracts (ongoing agreements, AMC schedules, loan terms).

Should migrate: 12–24 months of historical transaction data (enough for trend analysis and seasonal comparison), key documents (important contracts, compliance certificates, quality records), and performance benchmarks (sales targets, KPIs for comparison).

Leave behind: Data older than 3 years (store in archive, don't migrate), duplicate and incorrect records (migration is the perfect time to clean these), and data that was never reliable in the old system (migrating bad data creates ongoing problems).

The Tally Migration Challenge

Tally is the most common source system for Indian businesses. Tally's data structure differs from modern ERP in several important ways: chart of accounts concepts differ, GST treatment in older Tally versions doesn't map cleanly, and the concept of "parties" (combining customers and vendors) doesn't translate directly.

A well-designed Tally migration extracts: all ledger masters with balances, outstanding bills (receivable and payable), inventory masters with quantities, and party-wise transaction summaries. The migration script handles the structural transformation. What it can't fix is data quality issues in the source Tally data.

The Excel Migration Nightmare

Migrating from Excel is harder than Tally because Excel files have no enforced structure. Column names vary between files. The same customer appears with different names in different sheets. Some cells have formulas, others values, others formatting. The migration process for Excel-based businesses involves: discovery (how many Excel files contain business-critical data?), standardisation (building a canonical data structure), extraction (pulling data from each file into the standard), cleaning (resolving duplicates, correcting errors), and loading (importing clean data into the new system).

MNB Research's Excel migration methodology has processed data from businesses with 150+ spreadsheet files. The typical timeline: 3–5 weeks for data cleaning and migration for a business this size.

The Data Quality Audit (Before Migration)

Run a data quality audit before committing to a migration approach. Check: duplicate customers/vendors (common in businesses where different people enter data), inconsistent product codes (same product with 3 different item codes), outstanding balances older than 12 months (are these real or write-offs not yet recorded?), and inventory discrepancies (system stock vs. physical count). Clean the data in the source system before migration — it's easier to clean Tally data in Tally than to clean imported data in Odoo.