---
title: "How to Reset Invoice Numbering for FY 2027-28 (Rule 46 series)"
description: "On 1 April 2027 your invoice series can start again at 1. Here is what Rule 46 actually requires, how to choose a prefix that fits in 16 characters, and how to do the reset in billing software without breaking April's GSTR-1."
author: "Amresh Kumar"
published: 2026-09-09T05:00:16.817Z
updated: 2026-09-09T05:00:16.836Z
url: https://blog.mybillplease.com/new-financial-year-invoice-series-reset
---
# How to Reset Invoice Numbering for FY 2027-28 (Rule 46 series)

## Key takeaways

- Rule 46(b) requires invoice numbers to be unique within a financial year, so a reset on 1 April is allowed but not compulsory; continuing the sequence is also compliant.
- A financial year prefix such as INV/27-28/ makes every number self-identifying and keeps a reset from producing duplicates across years.
- Whatever you choose must fit in 16 characters including the prefix, use only letters, numbers, hyphen and slash, and run consecutively.
- Reset every document type that has its own series (credit notes, debit notes, delivery challans, receipt vouchers), and report the new ranges in GSTR-1 Table 13 for April.

The next financial year begins on 1 April 2027, and with it your invoice series can begin again at 1. This is the one moment in the year when an invoice numbering change is painless, because Table 13 starts fresh, no customer holds an invoice from the new series yet, and the IRP has no April document to collide with.

The rule behind it is short. Rule 46(b) of the CGST Rules requires a tax invoice to carry a consecutive serial number, not exceeding 16 characters, in one or multiple series, containing letters, numerals, hyphen or slash, and unique for a financial year. Everything else, including whether to reset at all, is a design choice.

This post explains what the rule requires, how to design a series that fits, how to perform the reset in billing software, and what to check in April's returns. For the format of the number itself, in full, see [GST invoice number format rules](/gst-invoice-number-format-rules).

## What Rule 46 actually requires

Four constraints apply to every tax invoice series.

Consecutive. Numbers run in order without gaps that cannot be explained by a cancelled document. Cancelled invoices are reported in Table 13 as cancelled; deleted invoices leave a gap the department may ask about.

Not exceeding 16 characters. The count includes every letter, number, hyphen and slash in the prefix and the serial. INV/2027-28/00001 is 17 characters and fails; INV/27-28/00001 is 15 and passes.

Only letters, numerals, hyphen and slash. Spaces, full stops, underscores and other symbols are not allowed.

Unique for a financial year. Within FY 2027-28, no two tax invoices from the same GSTIN carry the same number. Across years the rule is silent, which is why a reset is allowed; a year prefix simply makes cross-year uniqueness certain as well.

The same structure applies, series by series, to credit notes, debit notes, delivery challans, receipt vouchers, refund vouchers and bills of supply. Each has its own series and each series is reported separately in Table 13. The [GST invoice format guide](/gst-invoice-format-guide) lists the fields around the number.

![Creating a GST invoice in myBillPlease with HSN or SAC code, quantity, unit price, discount and tax rate per line](https://blog-media.cdn.byteinfy.com/media/6b/6bac44cde8e550f4165da9e5317b021e/original.webp)

*Pick the customer, add items with their HSN codes, and the tax split is worked out for you.*

> **Reset is permitted, not required**
> 
> Nothing in the rules forces a return to 1 on 1 April. A business that continues from 26-27's last number is compliant, provided the number stays unique and within 16 characters. The reset is a convention that keeps the year on the face of the document and keeps duplicate checks trivial.

## Reset or continue: choosing

Both options are compliant, so choose on practical grounds.

Reset with a year prefix when you issue enough invoices that a running number becomes long, when you want the financial year visible on every document, or when more than one system issues invoices and you need an easy duplicate guard. This is the default for most small businesses.

Continue the running number when your volume is low, your customers reference invoice numbers in their own systems and would be confused by a repeated serial, or you have contractual documents that cite a series that must keep running. Some businesses keep a running number but change the prefix, which gives both properties.

Whatever you choose, apply it to all series at once. A tax invoice series that resets while the credit note series continues is legal but makes Table 13 harder to read and creates a support question every time a credit note carries a higher number than the invoice it references.

## Designing the series

Start with what you need the number to say, then count the characters.

![Sales Invoices list in myBillPlease showing the INV/2627 series numbering](https://blog-media.cdn.byteinfy.com/media/dc/dc5eab06e0a8f537ad64c56f41f5ce12/original.webp)

| Pattern | Example | Characters | Room for invoices | Verdict |
| --- | --- | --- | --- | --- |
| INV/YY-YY/NNNNN | INV/27-28/00001 | 15 | 99,999 per year | Good default |
| INV-YYYY-NNNNN | INV-2027-00001 | 14 | 99,999 per year | Fine, year is start year only |
| BRANCHCODE/YY-YY/NNNN | DEL/27-28/0001 | 14 | 9,999 per branch | Good for multi-branch |
| INV/2027-28/00001 | INV/2027-28/00001 | 17 |  | Fails the 16 limit |
| 2728INV000001 | 2728INV000001 | 13 | 999,999 | Passes, but hard to read |
| 000001 | 000001 | 6 |  | Fails IRP check, starts with 0 |

Rules of thumb that avoid trouble:

- Count characters including slashes and hyphens. Sixteen is the limit for the whole string.
- Do not start the number with 0, slash or hyphen. The IRP rejects it, and it is a poor habit even below the e-invoicing threshold.
- Pad the serial to the number of digits you might need in a year plus one. A business issuing 300 invoices a month needs at least four digits; five is safer.
- Use a different prefix for each document type: INV for tax invoices, CN for credit notes, DN for debit notes, DC for delivery challans, RV for receipt vouchers, PI or QT for proforma invoices and quotations, which are not tax documents but still benefit from clear numbering.
- If you have multiple GSTINs, each registration has its own series. A prefix with the state code or branch avoids confusion when one office prepares returns for all of them.

## Series design check
- Whole string 16 characters or fewer
- Only A to Z, 0 to 9, hyphen and slash
- Does not begin with 0, slash or hyphen
- Financial year visible in the prefix
- Separate prefix per document type
- Separate series per GSTIN
- Serial padded for a full year's volume

## Step by step: resetting in billing software

The screens differ by product, but the sequence is the same. Do this in the last week of March, and switch on 1 April.

1. Close March. Issue every March invoice, credit note and challan before the switch, so the old series ends cleanly and its last number is known. Cancel anything that should not stand rather than deleting it.
2. Note the last number of each series. You will need them for March's Table 13 and to confirm the old series is not used again.
3. Open Settings, then the invoice or document numbering section. For each document type, set the new prefix (for example INV/27-28/) and set the next number to 1. Keep the padding.
4. If the software supports scheduled or financial year based series, set the effective date to 1 April 2027 so the change happens automatically at midnight. If it does not, make the change manually on the morning of 1 April before the first invoice.
5. Repeat for credit notes, debit notes, delivery challans, receipt vouchers and any other series you use. Do the same in any PDF template that hard-codes a prefix.
6. Update integrations. A marketplace connector, a Razorpay payment link flow, or a shipping integration that generates invoice numbers must use the new series from 1 April as well, or you will have two series in April.
7. Issue a test invoice on 1 April, confirm it reads INV/27-28/00001 (or your chosen format), then cancel it if it was only a test and record the cancellation. Some businesses prefer to make the first real invoice the test.
8. Communicate the change to customers who reconcile against your numbers, such as B2B buyers with purchase order systems.

In myBillPlease, the numbering lives in the document settings, with a separate prefix and next-number for each of the 14-plus document types, so the reset is one screen per series. Invoices created automatically from orders and from Razorpay payment links then pick up the new series without further changes.

_[form: gst-invoice-format-en]_

**Set up the new series before 1 April**
Create a free account at mybillplease.com/signup and configure a prefix and starting number per document type.

[Start free](https://www.mybillplease.com/signup)

## Documents that straddle the year end

A few cases catch people every April.

Credit notes in April against March invoices. The credit note gets an April number from the new credit note series and references the March invoice by its old number. Never renumber the original. Report the credit note in April's GSTR-1 Table 9B. The [credit note and debit note guide](/credit-note-debit-note-gst) covers the reference fields.

Goods dispatched on 31 March, invoice dated 1 April. Section 31 requires the invoice before or at the time of removal for goods, so the invoice date should be 31 March and the number from the old series. The e-way bill, if one is needed, references that invoice.

Services completed in March, invoiced in April. Permitted, because a service invoice may follow the supply by up to 30 days. It carries an April number from the new series and falls in April's return, though the supply itself belongs to FY 2026-27 for accounting.

Advances received in March for April supplies. The receipt voucher is dated March in the old series; the April tax invoice in the new series adjusts the advance.

| Situation | Document date | Series used | Return period |
| --- | --- | --- | --- |
| Goods dispatched 31 March | 31 March | Old, INV/26-27 | March |
| Goods dispatched 1 April, ordered in March | 1 April | New, INV/27-28 | April |
| Service done in March, invoiced 10 April | 10 April | New, INV/27-28 | April |
| Credit note in April for a March invoice | April date | New credit note series | April, Table 9B |
| Advance received 28 March, supplied 5 April | RV 28 March, INV 5 April | Old RV, new INV | March 11A, April Table 4 |

Proforma invoices and quotations. These are not tax documents and have no Rule 46 series, but resetting them at the same time keeps everything readable. The [proforma invoice guide](/what-is-proforma-invoice) explains why a proforma can never become the tax invoice by relabelling.

> **The invoice date decides the year, not the payment date or the order date**
> 
> An order placed on 30 March and shipped on 2 April is an April invoice in the new series. A Razorpay payment on 31 March for a service performed on 3 April is a March receipt voucher and an April invoice.

## April's GSTR-1: Table 13 after the reset

Table 13 of GSTR-1 lists the documents issued in the period, one row per series: nature of document, series from, series to, total, cancelled, net issued. After a reset, April's Table 13 shows the new series starting at 1. March's Table 13, filed by 11 April, shows the old series ending at its last number.

Two things to check before filing April:

- Every series that issued a document in April appears, including the credit note series if you issued credit notes against March invoices.
- The from number is 1 (or your chosen start), the to number equals the last April document, and total minus cancelled equals net.

If a system issued a stray March-format number in April, you will see two rows for tax invoices with overlapping ranges, which is the signal to correct the integration before May. The [GSTR-1 filing guide](/gstr-1-filing-guide) walks through the table.

## E-invoicing after the reset

For businesses above Rs 5 crore aggregate turnover, the reset interacts with the IRP in three ways.

Duplicate check. The IRP rejects a document number already registered for the same GSTIN, document type and financial year. A new prefix guarantees April numbers are fresh.

Format check. The IRP enforces the 16-character limit and the allowed characters, and rejects numbers beginning with 0, slash or hyphen. Test the first April invoice against the IRP rather than assuming the template passes.

Reporting window. If your aggregate turnover is Rs 10 crore or more, each invoice must be reported to the IRP within 30 days of its date. An April invoice missed during the changeover cannot be registered after 1 May. The [e-invoicing guide](/e-invoicing-guide) covers the mechanics.

## Mistakes we see every April

- Resetting the tax invoice series but not the credit note series, then issuing CN numbers higher than the invoices they reference.
- Adding the full year to the prefix (INV/2027-28/) and breaching 16 characters on the first invoice.
- Leaving a marketplace integration on the old prefix so April has two tax invoice series.
- Deleting the March test invoice instead of cancelling it, which leaves a gap in Table 13.
- Restarting a series mid-year after a software change, which creates duplicates within the same financial year, the one thing Rule 46 actually forbids.
- Forgetting the second GSTIN, so a branch continues the old series for weeks.

Each of these is easier to prevent than to correct, because a wrong number on an issued invoice cannot be edited; it needs a credit note and a fresh invoice. The [GST billing mistakes guide](/gst-billing-mistakes-small-business) covers the broader list.

- 1 April morning
- New prefix and next number set for every document type
- Old series confirmed closed at its last March number
- Integrations and PDF templates on the new prefix
- First April invoice checked for format and character count
- First e-invoice registered on the IRP, if applicable
- March GSTR-1 Table 13 prepared from the closed old series

**Generate a correctly numbered invoice for the new year**
The free invoice generator at mybillplease.com/tools/invoice-generator shows where the series sits on the document.

[Start free](https://www.mybillplease.com/tools/invoice-generator)

## FAQ

### Is it mandatory to reset invoice numbers on 1 April?

No. Rule 46(b) requires the serial number to be unique for a financial year and consecutive. Starting again at 1 with a new prefix satisfies that, and so does continuing the old sequence.

### What should the first invoice of FY 2027-28 be numbered?

A common pattern is INV/27-28/0001 or MBP-2728-00001. Pick a prefix that identifies the year, then a zero-padded number long enough for a year of invoices.

### Can I keep using the old series for a few days into April?

Invoices dated on or after 1 April 2027 belong to FY 2027-28, and their numbers only need to be unique within that year. Technically continuing the old sequence is fine.

### Do credit notes and delivery challans need their own reset?

Each document type has its own consecutive series under the rules, so each one is reset separately.

### How does the reset affect GSTR-1?

Table 13 of April's GSTR-1 lists each series used in the month with its first and last number. After a reset, April shows the new series starting at 1.

### What about e-invoices and the IRP after the reset?

The IRP rejects a duplicate document number for the same GSTIN and document type within a financial year. A new prefix guarantees no collision.

### Can I change the invoice format itself at the reset?

Yes, the start of a financial year is the cleanest moment to change a prefix, padding or series structure, because Table 13 starts fresh.