The due date creates the operating rhythm.
GST returns and payment are generally due one month after the end of the accounting period. A nil return is still required when there was no business activity. That means the review pack should be ready before the deadline, not assembled when the filing reminder arrives.
- Quarterly periods usually end Mar, Jun, Sep, and Dec unless special periods apply.
- Payment and filing are due one month after the accounting period.
- Nil activity still needs a nil GST return.
The pack should reconcile boxes to evidence.
The F5 boxes are only useful if the totals can be traced. Box 4 total supplies should reconcile to standard-rated, zero-rated, and exempt supplies. Box 5 taxable purchases should exclude GST. Box 6 output tax and Box 7 input tax should be tracked separately, with Box 8 showing the net difference.
- Sales listing by GST treatment and period.
- Purchase listing by input-tax treatment and blocked-input status.
- Source invoices, credit notes, debit notes, and adjustment evidence.
- A clear bridge from transaction totals to F5 boxes.
Exceptions need their own review lane.
The F5 review usually turns on exceptions: blocked input tax, partial exemption, timing questions, missing tax invoices, unusual zero-rated supplies, and corrections. These should not be hidden in a transaction list. They should be surfaced with the source document, proposed treatment, and reason.
- Blocked input tax and non-claimable GST.
- Partial-exemption apportionment and exempt supplies.
- Missing or invalid tax invoices.
- Corrections that may require F7 rather than an ordinary F5 adjustment.
How Accountant Included fits.
Accountant Included is being built to assemble the F5 review pack from coded transactions and source evidence. The agent drafts GST treatment, the review queue holds judgment calls, the reasoning log records the rule and confidence, and the audit trail preserves the approval. The product prepares the review pack; it does not transmit the return to IRAS.