Filing, period close & statutory reports

The obligation calendar

Obligations are generated from your active registrations crossed with rolling periods. Each one carries its statutory frequency, due date and reporting currency.

India

Return	Monthly filer	QRMP filer
GSTR-1	11th of the following month	13th of the month following the quarter
GSTR-3B	20th of the following month	22nd (Category X states) or 24th (Category Y states)
GSTR-9	—	31 December following the financial year (April–March)

The Category X / Category Y split is why jurisdiction normalisation matters: an unnormalised state string falls through to Category Y and moves the due date by two days — a missed statutory deadline, not a display bug.

Other regimes

Regime	Due date
UK VAT	One month and seven days after the period end
EU OSS	End of the month following the quarter
US sales tax	20th of the following month (state variations apply)

Due dates are not shifted for weekends. That is statutorily correct — the statute says the date, not the next business day. Government extensions are handled by a due-date override on the period, which the calendar honours.

The five-step close

Step	What it does
Compute	Every order in the period has a computation. Backfill historical periods here
Reconcile	Discrepancies in your blocking set are cleared
Prepare	Snapshots the liability, due date and FX rates for the period
Finalize	Locks the period. Requires the gate to pass and a second person
File	Record the filing reference and acknowledgement, or e-file directly

Prepare-all runs the prepare step across every open obligation at once, which is how a multi-state Indian merchant starts a month.

Safe-to-file gating

The gate answers "is it safe to file this?" and separates blockers from warnings.

Blocker	Why
Open reconciliations	In your policy's blocking set
Report not generated	A statutory return must exist before the period can be closed
Invalid registration	The tax ID does not validate
Missing buyer GSTIN on B2B (India)	B2B invoices without a counterparty GSTIN are rejected at the portal
Invalid or short HSN (India)	HSN codes missing or below the required digit count
Open blocker queries	An accountant query marked as blocking

Warning	Why
No registration for a jurisdiction with activity	You may have a nexus obligation
Unregistered supplies present	Tax charged where you are not registered
Unmapped products	Fallback tax classification was used
Outstanding balance	The portal will require payment before filing

The report-readiness check is scoped to the specific jurisdiction, so a state-27 return cannot satisfy the gate for state-29's period.

Nil periods skip the artefact checks — but declaring nil is itself guarded: a period with computed tax, or one already filed, cannot be marked nil.

Statutory reports

Report	Regime	What it is
GSTR-1	India	Outward supplies — B2B, B2C large, B2C small, credit and debit notes, HSN summary
GSTR-3B	India	The summary return, including reverse-charge
GSTR-9	India	Annual return
Sales register	India	The invoice-wise Excel your accountant validates before GSTR-1
VAT OSS	EU	One-stop-shop return
UK 9-box	UK	The standard VAT return boxes
US nexus	US	Nexus and liability by state

The sales register

The sales register is the accountant's working document: one row per invoice, with buyer name, buyer GST number, state and country, taxable value, and the CGST, SGST and IGST percentages and amounts split out.

Where an invoice carries a single tax slab the percentages are the clean statutory figures; where it mixes slabs they are blended — and either way the amounts reconcile exactly to the total. Zero-rated and exempt supplies appear with nil GST, and refunds appear as negative credit-note rows.

Credit notes are split, not netted

GSTR-1 places credit notes in their own tables rather than netting them into the invoice tables, while the summary and HSN sections net them. That is what the portal expects — and it is why the HSN table must net them too. An HSN section built from positive values only will not reconcile against the return's own summary, and the portal's cross-check rejects it.

Pre-file validation

Before you file, two validators run over GSTR-1:

HSN validation — flags missing, unspecified or too-short HSN codes
B2B GSTIN validation — flags counterparty GSTINs that do not match the 15-character structure

Both surface as gate blockers rather than as portal rejections a day later.

Export formats

Every report renders from a single view model into:

Format	Use
Excel	The accountant's working copy — real multi-sheet workbooks
PDF	A filing summary for records
CSV	Sectioned, with every section present
JSON	Machine-readable
Portal	GSTN offline-utility, HMRC MTD and EU OSS shapes

Reports are versioned: generating again supersedes the prior version rather than overwriting it, and each version carries a content hash and the currency it was rendered in. Every download is written to the audit log.

CSV exports are guarded against formula injection while leaving plain numbers untouched, so a value beginning with = cannot execute when the file is opened in a spreadsheet.

Payments, amendments and books

Feature	What it does
Payment ledger	Record remittances against a period; the outstanding balance is what the gate checks
Amendments	Post-close adjustments open an amendment period rather than reopening a filed one
Book reconciliation	Compare the return against your accounting system — manual, with adapters for Xero, QuickBooks, Tally and Zoho
Late charges	For India, section 50 interest and section 47 late fees are estimated on the net cash shortfall after input tax credit, not on gross output tax

Recording a filing requires an acknowledgement reference, and a period with an outstanding balance cannot be marked filed on a payable return — because the portal itself enforces pay-before-file.

Input tax credit and e-invoicing

Feature	What it does
GSTR-2B import	Import your input tax credit statement from CSV; available versus blocked credit is summarised
Consistency check	Compares GSTR-1 against GSTR-3B box by box, within a ₹1 tolerance
E-invoice registry	Import your IRN registry and reconcile it against B2B supplies, reporting coverage and flagging un-invoiced B2B

An import that parses to zero usable rows is refused rather than applied — a CSV with unrecognised headers would otherwise wipe the period's ledger and turn into a false under-claim.

Accountant workflow

Feature	What it does
Assign a reviewer	Route a period to your accountant
Query thread	Raise and resolve questions against the period
Sign-off	Name plus professional membership number, recorded on the period
Buyer GSTIN directory	A counterparty registry with CSV import, matched onto invoices at report time

The buyer GSTIN directory enriches reports at generation time by matching on customer ID, then email, then legal name. It never rewrites the immutable computation — enrichment is a reporting-layer concern.

Sign-off requires a finalised period with no open blockers.

Portfolio view

For merchants filing in several jurisdictions, the portfolio header gives an FX-normalised roll-up: how many periods are closed out of how many, total outstanding, and late exposure broken down by state.

Evidence packs

One click produces a ZIP containing a manifest, the generated reports, and CSVs of the period's computations, reconciliations, payments and audit entries.

This is the artefact you hand to an auditor. It is generated from stored data rather than recomputed, so it reflects what was actually filed.

Plan tiers

Capability	Free	Starter	Pro	Agency	Enterprise
Obligation calendar and close	—	—	✓	✓	✓
Safe-to-file gate	—	—	✓	✓	✓
Statutory reports, all formats	—	—	✓	✓	✓
Payments, amendments, book reconciliation	—	—	✓	✓	✓
ITC import and consistency check	—	—	✓	✓	✓
E-invoice reconciliation	—	—	✓	✓	✓
Accountant review and sign-off	—	—	✓	✓	✓
Evidence packs	—	—	✓	✓	✓
Multi-jurisdiction portfolio	—	—	✓	✓	✓

Best practices

Prepare early in the month, not on the due date. Prepare snapshots the liability and FX rates; doing it late means diagnosing a blocked gate under time pressure.
Generate the sales register before GSTR-1. It is the document your accountant will actually check, and errors are cheaper to find there.
Import GSTR-2B every period. Without it, the credit side of the return is a guess.
Never mark nil to get past the gate. It is guarded, and the guard is there because filing real liability as nil is a serious matter.
Keep the evidence pack. Regenerating one years later is possible; having it at the time is better.

The obligation calendar​

India​

Other regimes​

The five-step close​

Safe-to-file gating​

Statutory reports​

The sales register​

Credit notes are split, not netted​

Pre-file validation​

Export formats​

Payments, amendments and books​

Input tax credit and e-invoicing​

Accountant workflow​

Portfolio view​

Evidence packs​

Plan tiers​

Best practices​

See also​