A switch of accounting software is feared for one reason: the fear of arriving on the other side with a number missing. KRONENWERK's Migration Center is built around that fear. It reads the exports of the product you are leaving — CSV or XLSX, including the zip archives QuickBooks Online produces — takes customers, suppliers, sales invoices, credit notes, bills, expenses, payments, documents, the chart of accounts and the opening balance, shows you every total before anything is written, and writes into the books only when you approve exactly what you saw. Until you touch an imported record, the whole import can be reversed. For most small businesses the work is one afternoon once the exports are in hand, and the accountant who used to hold the spreadsheet can keep working with you from inside KRONENWERK.
Three kinds of switch
- From another product
- QuickBooks, Xero, Wave, lexoffice, sevDesk, a French or Belgian package — anything that exports its lists as CSV or XLSX. KRONENWERK recognises QuickBooks' exports by their shape; every other product goes through the generic adapter, where you say once what each column is.
- From your accountant's spreadsheet
- Many businesses do not have accounting software at all; they have an accountant who keeps a spreadsheet and a folder of PDFs. The spreadsheet is a CSV. The folder of PDFs is a set of documents the Migration Center attaches to the invoices and bills they belong to, by number — never by guessing.
- From paper and a bank statement
- No export exists. You enter the opening balance as of a date, start issuing invoices and recording bills from that date, and file the old paper as documents against the opening balance. The AI assistant makes this the fastest of the three: photograph, say what it is, confirm. See accounting with AI.
What moves, and what it becomes
| From the old system | In KRONENWERK | Note |
|---|---|---|
| Customers, suppliers | Partners with address, VAT ID, currency, e-mail | Duplicates by name or VAT ID are shown before commit, not merged silently. |
| Sales invoices, credit notes | Imported invoices in the archive, marked as imported | No PDF is regenerated; the original file can be attached. An imported invoice is not cancelled by KRONENWERK — it was not issued here. |
| Bills, expenses | Purchase records with the figures as printed | With their files where the export carries them. |
| Payments against bills and expenses | Payments | A partial payment against a sales invoice cannot be imported as a settlement; the outstanding amount is taken from the export's column instead, so receivables are right. |
| Documents | Attachments on the record they belong to | Matched by number only. A document that matches nothing stays unmatched and is listed. |
| Chart of accounts | The company's chart | Account type is required, never guessed from a name. |
| Opening balance | The opening entry on the switch date | Committed as a set that must reconcile. |
| Products | Staged only | Shown for checking; not yet committed. |
| Journal entries, bank transactions | Staged only, deliberately | The invoices of the same period are already imported and the opening balance says where they left the accounts; posting the journals too would state revenue twice. |
The seven steps
- Export. In the old product: customers, suppliers, invoices, bills, expenses, payments, documents, chart of accounts, and a trial balance as of your switch date. QuickBooks Online: Settings → Export data, which produces a zip of XLSX files. Everything else: CSV.
- Upload. Settings → Migrations → new migration. Drop the files in; each is kept as evidence of what was attempted, unchanged.
- Detect and map. KRONENWERK names the adapter it recognised or asks you to choose. For each file you see the columns and pick what each one is. Dates written with dots are read day-first, always — no locale writes
08.23.2026; slashes are asked about once. - Validate. Every row is checked: a customer without a name, an invoice without a date, a VAT ID that cannot be one, a total that does not add up. Rows that fail are listed by line, and nothing proceeds until they are fixed or excluded.
- Preview and reconcile. Counts and totals per file — how many invoices, how much outstanding, the opening balance's two sides — beside the figures your old system printed. This is the moment to compare against the trial balance you exported.
- Approve and commit. Your approval is tied to exactly the staged state you saw, down to every row; if anything changed in between, the commit is refused and you look again. A bookkeeper can prepare and map; the owner reviews the totals and commits. The phone cannot map, approve or commit — deliberately.
- Report. What was written, what was skipped and why, what could not be matched. Keep it with the migration's files.
Reversal
Before commit, discard: the staging goes, the uploaded files stay, the books were never touched. After commit, while nothing imported has been touched: full reversal, every record removed in reverse order, only where it is still exactly as imported. Once anything has been touched — a payment recorded against an imported bill, a document attached to an imported invoice, an edit — no reversal, ever; from then on corrections are ordinary corrections. The rule is stated on the migration page so nobody discovers it afterwards.
Keeping your accountant
Switching software does not mean switching accountants. You invite the practice into your company; with the practice plan it sees every client it is engaged for on one screen and steps into any of them, with the rights you gave. Your company stays your company — its own books, its own owner — and you end the engagement, not the practice. What the accountant used to reconstruct from your papers at quarter's end is already in the books when they open them, with the files on the record they belong to.
Switching in-house from an accounting firm
If the firm did the bookkeeping for you and you want to do it yourself now, the honest sequence is: get the closing figures from the firm as of a date — the trial balance, the list of open customer invoices and open supplier bills — and import exactly those as the opening position. Start issuing and recording in KRONENWERK from that date. Do not try to re-key the old years; attach the old year-end statements as documents against the opening balance instead. From day one an AI assistant can do the typing you were paying for, and the firm can be invited back for the year-end alone.
How long it takes
Exporting: an hour, mostly finding the buttons. Mapping and validation: an hour for a clean export, an afternoon for a messy spreadsheet. Reconciling: as long as it takes to make the outstanding total match the old system's — usually minutes, occasionally the discovery of an invoice the old system had counted twice. Commit: seconds. What takes longer is deciding the switch date; the first day of a quarter is the usual answer, because the trial balance is easiest to get on that day.
How KRONENWERK handles this
SUPPORTED WITH LIMITATIONS The Migration Center reads CSV and XLSX, recognises QuickBooks Online exports, commits customers, suppliers, sales invoices, credit notes, bills, expenses, payments against purchases, documents, chart of accounts and opening balances, stages products, journal entries and bank transactions for checking without committing them, and reverses a whole migration until an imported record is touched. The full Migration Center is included from the Business plan; a basic import is in every plan. Dedicated adapters for lexoffice, sevDesk, DATEV and Xero are not built yet — their exports go through the generic adapter with a one-time mapping. See pricing and, for a migration driven by your own code, the accounting API.
Frequently asked questions
Do I lose my invoice numbers?
No. Imported invoices keep the numbers they were issued under, marked as imported. New invoices continue from the number you set as the next one.
Can I import several years?
You can import as many years of invoices and bills as the export holds; they become records in the archive. Only the opening balance carries balances into the ledger, so history stays history and the current year posts cleanly.
What if the old system's export is a mess?
Validation lists every row that fails with the reason. A formula that survived the export is stored unchanged and flagged; an ambiguous date is asked about once. Nothing is silently corrected.
Can my accountant do the migration for me?
Yes. Prepare, upload and map need the migration rights; the commit needs the owner's approval, so the practice can do the work and you sign.
Is there a QuickBooks import?
Yes. QuickBooks Online exports a zip of XLSX files and no CSV; KRONENWERK reads the zip, recognises the lists, and tells you which files are reports rather than lists so a subtotal row never becomes a customer.
What about my bank?
Bank transactions can be staged for checking but are not committed; the opening balance carries the bank balance. Statements are imported for reconciliation from then on.