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quiz vs the machine

Gold1440

System Design

The Reconciliation Deep Dive

Comparing your internal ledger against external statements to catch divergence early.

5 min read · core · beat Gold to climb

What reconciliation does

Reconciliation compares your internal ledger to an external source of truth such as a bank statement or a processor report. The goal is to confirm that every movement you recorded actually happened externally, and that nothing external is missing from your books.

The matching problem

Each side has its own records with different identifiers and timing. Reconciliation matches entries by amount, date, and a shared reference, then flags anything that does not pair up.

Three outcome buckets

  • Matched entries appear correctly on both sides.
  • Internal only entries are in your ledger but not the statement, often timing or a phantom write.
  • External only entries are on the statement but missing from your ledger, often a dropped event.

Operational guidance

  • Run reconciliation on a fixed cadence like daily so breaks surface fast.
  • Treat unmatched items as exceptions that a human or rule must resolve.
  • Track the break age so old discrepancies escalate.

Key idea

Reconciliation matches your ledger against external records so divergence is caught and resolved before it compounds.

Check yourself

Answer to earn rating on the learn ladder.

1. What does an external only entry usually indicate?

2. Why run reconciliation on a fixed cadence?