A CSV RECONCILIATION WALKTHROUGH · 6 NOVEMBER 2026
Compare invoice and payment CSVs, including partial payments.
When an invoice export and a payment export share a reference, you can compare them without uploading financial records or rebuilding a spreadsheet formula every time. The useful result is a list of exceptions, with enough evidence to investigate each one.
This walkthrough uses invented USD records. Download the invoice CSV and the payment CSV, or explore the interactive example.
1. Make the two exports comparable.
Export each source as CSV UTF-8. Check the reporting period, filters, sign convention and amount basis first: a gross invoice total will not necessarily equal a payout after fees. Keep currencies separate. If an invoice number is only unique within a supplier, use supplier plus invoice number as the key on both sides.
CrossTally Desk accepts CSV and TSV. Export XLSX files as CSV UTF-8 first. Keep references such as 001042 as text when exporting; a missing leading zero cannot be recovered automatically.
2. Map the common reference and amounts.
In the downloaded CrossTally Desk application, choose the invoice file as A and the payment file as B. For these samples, select invoice as the reference, amount as the amount, and currency as the currency on both sides. Choose the decimal-point format because the samples contain values such as 240.00.
Use the format of each actual export. An amount written as 1.234,56 needs a different decimal format from 1,234.56. An unreadable row belongs in the exception list; silently converting it to zero would hide a problem.
3. Review repeated references before grouping.
Start in Strict mode. The two payment rows for INV-1042 have the same reference, so Strict mode flags a repeated key. Inspect them before choosing Group payments.
If they are two legitimate instalments, $200 and $150 together settle the $350 invoice. Grouped mode sums rows sharing the selected key and currency. If one row is an accidental duplicate, grouping would also add it: the source evidence still needs your review.
| Reference | Invoice | Payment export | Grouped result |
|---|---|---|---|
| INV-1041 | $240.00 | $240.00 | Exact match |
| INV-1042 | $350.00 | $200.00 + $150.00 | Exact match after grouping |
| INV-1043 | $480.00 | $475.00 | $5.00 difference |
| INV-1044 | $125.00 | No corresponding row | Invoice only |
4. Investigate the differences.
The $5 difference for INV-1043 might be a fee, a short payment or an export issue. The files alone do not tell you which. INV-1044 is absent from the supplied payment export; check the date range and the source system before concluding that it is unpaid.
The invoice export totals $1,195 and the payment export totals $1,065. The $130 gap is explained here by the $5 difference and the $125 invoice-only record. Equal overall totals in another reconciliation would still not prove that every individual record matched.
5. Keep the evidence.
Export a CSV summary for the exception list, or an HTML/JSON report with source rows and comparison rules. Keep invalid rows visible. Save the column mapping for the next comparable export. Reports can contain original financial records, so choose their recipients deliberately.
Use a local file for the recurring task.
CrossTally Desk 0.1.0 runs as an HTML file in Chrome on Windows. It supports one or two keys, explicit grouping, separate currencies and evidence reports. It has no bank connection, fuzzy matching or currency conversion. The delivered version costs $39 once for one user, plus applicable tax shown at checkout, with a 14-day refund period.