This article covers why a document's period in iplicit can differ from the month of the date entered on it. This happens because of how the 'Period calculation min' setting interacts with the document date, and applies to the Sales Ledger, Purchase Ledger and other document types using this setting.

How the period is calculated

When a document type's 'Period calculation min' is set to 'Financial year group: default period', the document date and the default period both play a part in choosing the period:

  • If the document date falls on or after the default period, the document uses the period matching its own date
  • If the document date falls before the default period, the document uses the default period instead, not the earlier period matching its date

For example, if the default period is set to July 2026:

  • A document dated in August 2026 uses August 2026, because August is after the default period
  • A document dated in July 2026 uses July 2026, matching the default period
  • A document dated in May 2026 also uses July 2026, not May 2026, because May falls before the default period

Earlier periods, such as May or June in this example, don't need to be closed for this to happen. The default period acts as a floor - documents dated before it are pulled forward to it, even while those earlier periods remain open.

Why this matters

This is the same behaviour that's always applied to the Financial Year Group's overall default period, now also available separately for the Sales Ledger and Purchase Ledger. For setting these up, see 'How to set default posting periods for the Sales Ledger and Purchase Ledger'.

Things to know

  • This only applies to document types with 'Period calculation min' set to 'Financial year group: default period'. Document types set to 'Open periods' aren't affected
  • Moving the default period forward changes the floor for new documents from that point on. It doesn't retroactively change documents already posted.
Customer search terms

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