01 / Source data
The first problem is understanding what each value means
A date is not always value date
A statement may include booking, operation and value dates. If only one exists, you need to understand its meaning before mapping it.
Amount is not always balance effect
Some exports split debit and credit; some use a signed amount; others add a separate fee that also changes balance. The normalized movement must reproduce the real effect.
One file can contain several ledgers
A single export can group products or accounts with independent balances. Merging them into one Norma 43 account can create a plausible-looking but incorrect reconciliation.
Currency and precision are data too
Currency should not be silently assumed, and some exports may contain sub-cent source values. Norma 43 stores amounts at the precision defined by its record format.
02 / Mapping
Minimum mapping before generation
A column name is a hint, not proof of semantics. Before generation, normalize each movement and check it against source running balance whenever that evidence exists.
- Identify operation date and, when present, value date.
- Determine whether amount is already signed or debit/credit is represented in separate columns.
- Apply fees only with observed semantics; do not flip a sign simply because it looks more convenient.
- Keep concept text and source sequence when running balance depends on statement order.
- Detect currency from unambiguous evidence or require confirmation; do not infer a specific currency from an ambiguous symbol.
- When a file includes multiple accounts or products with their own balances, process each scope separately.
03 / Norma 43
What the resulting Norma 43 file must represent
Bank-hosted Cuaderno 43 documentation defines 80-character records for describing accounts and their movements. In the flow implemented by N43 Bridge, record 11 opens the account, 22 represents a movement, 23 extends concepts, 33 closes the account with counts, totals and closing balance, and 88 closes the file. Checking that text exists is not enough: fields, widths, totals and balances must reconcile.
Checks worth applying to the generated file
- Every record has exactly the width expected by the format.
- The header identifies account, period, opening balance and currency coherently.
- Movements preserve dates, debit/credit sign, amount and references in the intended fields.
- The account footer agrees with debit/credit counts and totals and with the reconstructed closing balance.
- The file footer reports a record count consistent with the generated content.
04 / Validation
Validate before download with N43 Bridge
N43 Bridge applies this flow locally in the browser: it imports XLS, XLSX or CSV, lets you review mapping, normalizes movements, reconciles balances and enables generation only after the required prerequisites are satisfied.
- Generates records 11, 22, 23, 33 and 88 and validates record width, count, debit/credit totals and closing balance.
- Validates Spanish IBAN or CCC locally and derives N43 account fields without silently coercing non-Spanish identifiers.
- Opening balance is auto-applied only when multiple running-balance checkpoints reconcile; other cases require explicit confirmation.
- An imported running-balance mismatch blocks generation rather than appearing as a warning only.
- Mixed currencies are rejected within the current single-account scope.
- A real N43 generated from a privately validated statement has been cross-checked by two independent parsers without turning that test into an ERP compatibility claim.
05 / Checklist
Checklist before importing N43 into accounting software
- 01
Confirm the account, currency and movement scope being converted.
- 02
Review date, amount, sign, fee, concept and running-balance mapping.
- 03
Verify that opening balance plus movements explains closing balance.
- 04
Do not merge products or accounts with independent balances.
- 05
Validate structure, record count and totals after generation.
- 06
Keep the original statement and compare a sample of movements with the generated N43.
- 07
Run a test import in the target accounting product before claiming compatibility.
06 / ERP compatibility
A structurally valid N43 does not guarantee compatibility with every ERP
Sage 50, A3 or any other importer is a separate acceptance layer. A file can respect the implemented structure and still need adjustments to references or conventions interpreted differently by a specific application. N43 Bridge does not advertise universal compatibility until a real import into the target software has been observed and compared.