How to Convert DB2 to QuickBooks

I’ve helped businesses pull their books off systems most people forgot existed — green-screen apps on an AS/400, custom software a retired programmer built in the 90s. The data almost always lives in an IBM Db2 database. Getting it into QuickBooks is very doable; it just has to be done in the right order.

What does it mean to convert DB2 to QuickBooks?

Db2 is IBM’s relational database. It stores data — it doesn’t “do” accounting on its own. When a business says they’re on “DB2,” they usually mean a custom or legacy accounting application whose numbers are stored in Db2 tables, often on an IBM i (AS/400) or mainframe.

So converting DB2 to QuickBooks isn’t swapping one accounting package for another. It’s a data migration: extracting the financial records out of the Db2 database and importing them into QuickBooks in a clean, reconciled form. That takes someone who understands both the source data and the accounting on the other side.

What data comes across

You don’t move the database — you move the financial records inside it. On a typical migration, that means:

• Chart of accounts — your general-ledger structure, remapped to QuickBooks.
• Customer and vendor master records and their contact details.
• Open accounts receivable and payable — unpaid invoices and bills.
• General-ledger balances and the transaction history you choose to keep.

The data is pulled from the Db2 tables using SQL queries or exports, then mapped to QuickBooks. Because a custom schema rarely matches QuickBooks one-to-one, this is careful mapping work, not a copy-paste.

How to convert DB2 to QuickBooks, step by step

1. Map the schema. Work out which Db2 tables and fields hold your accounts, customers, invoices, and balances. This is the make-or-break step.
2. Reconcile the source. Confirm the numbers in the legacy system are actually right before you move them. Garbage in, garbage out.
3. Extract the data. Pull the records with SQL queries or exports (CSV/IIF), keeping structure and relationships intact.
4. Map and import. Translate the data into QuickBooks’ format — chart of accounts, lists, open items, and balances — and import in the right order.
5. Reconcile and verify. Tie the trial balance, AR, and AP in QuickBooks back to the legacy figures, to the penny.

Most projects pair a technical resource who knows the Db2 side with an accounting pro who owns the QuickBooks side. Our QuickBooks conversion services cover the accounting half end to end.

Which QuickBooks should you land on?

Not every business needs the same edition. Match the tool to your size:

If you’re coming off a heavy legacy system, QuickBooks Enterprise usually has the headroom you need; smaller shops may be happier on QuickBooks Online. We’ll recommend the right one during scoping.

Benefits of moving off Db2 to QuickBooks

• Retire aging hardware. No more nursing an AS/400 or mainframe nobody wants to touch.
• Easier to staff. Most bookkeepers know QuickBooks; almost none know your custom Db2 app.
• Lower running cost. No DBA, no niche consultant, no custom-code maintenance.
• Modern, real-time reporting instead of overnight batch jobs.
• A supported, connected ecosystem of apps and integrations.

Common mistakes to avoid

• Guessing at the schema. Custom Db2 apps are undocumented more often than not. Confirm which tables hold what before extracting.
• Skipping source reconciliation. If the legacy numbers are wrong, migrating them just makes the error official.
• Dumping raw exports. Data must be mapped to QuickBooks’ structure, not force-fed. The two don’t match one-to-one.
• Over-scoping history. Bringing every transaction since 1998 is expensive and rarely needed. Scope it.
• Going live mid-period. Cut over at period- or year-end to avoid split reporting.

Best practices for a clean migration

• Document the Db2 tables and fields before you touch anything.
• Reconcile the legacy trial balance to the penny first.
• Decide how many years of history you actually need.
• Import in order: chart of accounts, lists, opening balances, then transactions.
• Verify AR, AP, and the trial balance in QuickBooks against the source.
• Keep a read-only archive of the Db2 data for compliance.

Why work with Numerawise Solutions

Migrating DB2 to QuickBooks lives at the seam between IT and accounting, and that’s exactly where projects fail. At Numerawise Solutions, we own the accounting side: we map your general ledger, translate customers, vendors, and open items into QuickBooks, and reconcile every balance back to your source, coordinating with your technical resource on the raw Db2 extraction. We’re QuickBooks specialists and Intuit ProAdvisors, so your new file is set up right — and our bookkeeping services keep it accurate long after go-live.

The bottom line

To convert DB2 to QuickBooks, remember what you’re really doing: lifting your financial data out of a legacy database and rebuilding it cleanly in modern accounting software. Map the schema, reconcile the source first, extract carefully, and verify every balance on the other side. Done right, you retire aging hardware, make your books far easier to run and staff, and gain reporting your old system could never touch — without losing a cent of history.

Key takeaways

• DB2 is IBM’s database, not accounting software — converting it to QuickBooks is a data migration.
• The financial records are extracted from Db2 tables via SQL or exports, then mapped to QuickBooks.
• Map the schema and reconcile the source before you move anything.
• Pick the right QuickBooks edition for your size and scope your history.
• Verify the trial balance, AR, and AP in QuickBooks against the legacy figures.