Document Numbering

Document Numbering checks the numbers your business issues and answers the five questions an auditor asks about any sequence: is a number missing, is a number used twice, is a document unnumbered, is a number out of order, and was a document deleted. A gap in an invoice sequence is the classic sign that a document left the books, so accountants usually run this check before anything else at a month end or year end.

The screen reads your numbers; it does not change them. To change how numbers are given out, see Preferences: cheque numbers are set on Write Cheques, and invoice and estimate numbering in the web Back Office.

Opening the screen

• Company ▸ Document Numbering

What is checked, and what is not

SeroBooks checks only the numbers it allocates itself, because only those run in a sequence:

A NOT CHECKED card at the foot of the screen names what is deliberately left out and why:

• Supplier bills and debit notes — the reference on a bill is the vendor's own invoice number, not a sequence you allocate, so a gap in it means nothing.

Estimates are not part of any checked series.

How numbers are grouped into series

The last run of digits in a number is its place in the sequence, and whatever comes before or after it names the series. So 2026/07/1230 is number 1230 of the series 2026/07/, and CM-67 is number 67 of the series CM-. A credit memo numbered 31842-R and one numbered Cr.Nt.-67 therefore sit in separate series and are never compared with each other. A number with no digits at all counts as no number.

A series needs at least three different numbers in the period before gaps and order are checked; one or two numbers prove nothing about a sequence.

Gaps at the edge of a period are not gaps

When you check September, invoice 399 may be in August and 451 in October. SeroBooks compares the period's numbers against every number the business holds, of any date, so only numbers that exist nowhere in the books are reported as missing.

The screen

The header shows Numbering, the count N documents checked, a period bar and Refresh.

The verdict

A card at the top gives the answer before the detail:

• Every number accounted for (green) — for example 1,240 documents across 3 series, with no gap, no duplicate and nothing unnumbered.
• N things to look at (red) — the count of missing numbers, duplicates and unnumbered documents.

To the right, each series that had documents in the period shows its count, such as 1,102 Sales invoices.

Numbering changes and deletions are shown below the verdict but are not counted as things to look at: a renumbering is not a problem, and a deletion is already recorded.

The findings

Each kind of finding has its own card, with a coloured dot, a count, and a sentence saying why it matters. A card only appears when it has something in it.

How SeroBooks tells a gap from a numbering change: a hole of 50 numbers or fewer is reported under Missing numbers; a wider one is treated as the start of a new block of numbers and reported under The numbering changed. Very long gaps are shown as a range rather than one number at a time.

Deleted in this period comes from the activity log and lists deletions made during the period's dates, with who made them. It is the other half of a gap: the sequence says a number is gone, and this says who removed it.

Working through the findings

1. Run the check for the period you are closing.
2. For each Missing number, look in the Deleted in this period card and the Audit Trail for the same number. A deletion with a reason is explained; one without is a question for whoever made it.
3. For each same number twice, open both documents. If one is the same sale entered twice, void or delete the extra one (see Edit, copy, void or delete an invoice). If both are real, note which is which for your accountant, because whichever number is quoted, the other document cannot be found by it.
4. For each no number at all, open the document to identify it. Unnumbered documents usually come from an import or another system; note them for your accountant.
5. For each out of order line, check that the backdating was intended. A higher number dated earlier is legitimate for a correction, but it is also how a document slips into a period that was already closed.
6. When every finding is explained, close the period in Set Closing Date and Year-End.

Related reports

• Invoice Number Gaps and Repeats (Reports ▸ Accountant & Taxes) lists missing invoice and credit memo numbers and numbers used twice, with the columns Series, What, Numbers, How many and Between. It is a report you can memorise, print and export; the Document Numbering screen covers more series and adds blanks, order and deletions.
• Voided/Deleted Transactions Summary and Detail, Audit Trail Report and Possible Duplicates in the same submenu. See Accountant & Taxes reports.
• Missing Cheques (Reports ▸ Banking) checks cheque numbers, which this screen does not.

Permissions

Anyone whose role can see Accounting reports can run the check. It changes nothing, so it has no action rights of its own.

Common problems

• Hundreds of numbers are missing after moving from another system. On imported books, missing numbers are usually documents that were never imported. Check whether they fall before your conversion date.
• A new block of numbers shows as missing numbers. Only jumps wider than 50 are treated as a numbering change. A smaller jump is listed under Missing numbers; note the reason for your accountant and move on.
• Bills are not in the report. By design: a bill's number is the vendor's, not yours. See the NOT CHECKED card.
• An invoice I parked or saved as a draft is not listed. Drafts and parked sales have not been issued and have no number yet.
• The check says it could not run. The message Could not check the numbering means the server could not complete it; choose Refresh to try again.