Self Invoice: the rules, and the document people confuse it with

Self Invoice: the rules, and the document people confuse it withA plain explanation of self invoice — what it is for, who issues it, what goes on it, and what happens if the wrong one is used.

What every one of them has in common

Whichever document it is, three things apply. It needs a consecutive serial number unique within the financial year, of not more than sixteen characters and using only letters, numbers, hyphens and slashes. It needs identifying content for both parties. And it has to be retained for the prescribed period, which is counted from the due date of the annual return rather than from the date on the document.

Each document type also needs its own series. A proforma numbered in your tax invoice series is a genuine problem, because it consumes a number from a series that has to be consecutive and complete.

Rates, turnover thresholds, e-invoicing applicability and the time limits for issuing all change. Nothing on this page states one as a current fact — check the notification in force for your own circumstances.

Self-invoicing: when you issue the invoice for your own purchase

There is a case where the buyer raises the invoice, and it is not a quirk — it is required. Where a registered person receives a supply that attracts reverse charge from a supplier who is not registered, there is no supplier invoice to be had. The recipient issues one themselves for that inward supply.

This is self-invoicing, and it exists because the tax liability has moved to the recipient and the paperwork has to follow it. Without the document there is nothing supporting the tax you are about to pay or the credit you may be entitled to.

A self-invoice carries the same identifying content as a tax invoice, with the recipient as the issuer, and it needs its own consecutive series kept separately from your outward invoices. Where payment is made for such a supply, a payment voucher is the companion document.

Which supplies attract reverse charge, and when consolidated self-invoicing is permitted rather than one document per supply, have both been changed by notification. Confirm the position currently in force rather than working from an older list — this is an area that has moved.

Issuing these properly, free

Tax invoices with the complete prescribed field set, tax split per line.
Bills of supply for exempt and composition supplies, with no tax line.
Proformas and quotations in their own series, converting to an invoice without retyping.
Credit and debit notes that reference the original invoice rather than editing it.
Separate consecutive series per document type, issued centrally so a number cannot repeat.
Tax derived from the place of supply, so CGST/SGST against IGST is never a judgement call.
A receivables position — what is unpaid, how old, and whose.
Export of everything to CSV, Excel and JSON, on every plan.
₹0 on the free plan, no card, no expiry.

Setting up your document series

Start free now — email and password, no card.
Enter your business name, address and GSTIN once.
Set the next number for your tax invoice series, carrying on from whatever you last issued.
Give proformas and quotations their own prefix, so they can never consume an invoice number.
Do the same for credit notes and for bills of supply if you make exempt supplies.
Add your customers with their GSTINs, and your items with HSN or SAC codes and rates.
Raise one of each document you actually use, and check the numbering behaved as you expected.

Timing: when the document has to exist

Issuing the right document late is its own problem, separate from issuing the wrong one. The time of supply decides when tax becomes payable, and the invoice date is one of the inputs to it — so an invoice raised whenever it is convenient can move a liability into a period you have already filed.

The limits differ by what is being supplied. For goods the trigger is tied to removal or delivery; for services it is tied to completion of the supply, within a prescribed number of days. Continuous supplies, supplies on approval and reverse-charge supplies each have their own rule.

The practical version of this is unglamorous: raise the invoice when the supply happens, not when the customer asks for it, and not in a batch at month end because that is when someone has time.

These limits have been amended before. Check the one applying to your type of supply rather than relying on a remembered number of days.

Keeping the documents for as long as you have to

Invoices and the records behind them must be retained for a prescribed period counted from the due date of the annual return for that year, not from the date on the document — so the obligation runs considerably longer than most people assume. Check the period currently in force for your own case.

That has a practical consequence. A laptop, a phone and a folder of PDFs are not a retention plan, because the horizon outlasts most hardware and most staff. Where records are kept electronically they have to stay accessible and readable for the whole period, which means a format you can still open and a copy somewhere other than the machine that produced it.

It is also worth keeping them in a form that can be searched and totalled, not only read. When records are actually asked for, the request is rarely "send me invoice 412" — it is a period, a customer or a figure that has to be reconciled.

Dull, cheap to do, and expensive to reconstruct. Those three things together are why it is worth doing now rather than later.

Reverse charge, exports and the supplies that behave differently

Not every supply is a straightforward taxable sale. Some notified supplies put the tax liability on the recipient rather than the supplier. Exports and supplies to an SEZ can be made under a bond or LUT without payment of tax, or with tax and a refund claimed afterwards. Composition dealers cannot charge tax at all and must say so on the bill.

Each of these changes what the invoice has to say — the reverse charge marking, the LUT reference, the "composition taxable person" declaration. They are not exotic cases; most businesses hit at least one.

The fields are on the invoice in Billixo whether or not you use them, so the day you need one you are not looking for a workaround.

What a GST invoice legally has to carry

Rule 46 of the CGST Rules sets out what a tax invoice must show, and it is a longer list than most invoice templates carry. Getting one field wrong does not usually cost you anything the day you raise it — it costs your customer their input credit months later, which is a harder conversation.

The fields are:

Your name, address and GSTIN
A consecutive invoice number, unique within the financial year
The date of issue
The customer's name, address and GSTIN where they are registered
Place of supply, and the state code, for inter-state supplies
HSN or SAC against every line
Description, quantity, unit, rate and taxable value per line
Rate and amount of CGST, SGST/UTGST, IGST and cess, shown separately
Whether tax is payable on reverse charge
Signature or digital signature of the supplier or an authorised person

Billixo fills these in from the customer and product records rather than asking you to remember them, which is the only reliable way a busy counter gets them all right every time.

Bill scanning, in practice

The single largest time cost in most small businesses is not raising invoices — it is entering purchases. A photograph of a supplier bill goes in and a structured draft comes out: supplier, GSTIN, line items, rates, tax split and total.

You check it. That is the workflow, and it is deliberate: an extraction you did not read is a liability, not a saving. But checking a filled form takes fifteen seconds and typing one takes three minutes, and that difference compounds over a month of purchases.

Who it is built for

Small and mid-sized Indian businesses that are registered under GST and bill regularly. One person doing everything, or a counter with three people billing at once and an accountant who needs the month to close cleanly.

The design assumption throughout is that whoever raises the invoice is busy and is not a tax specialist. So the tax is computed rather than asked for, the compliance fields are populated rather than presented as questions, and the report the accountant wants is a download rather than a request.

Try it free — the free plan needs no card and does not expire.

Free, and what it costs you instead

Free software usually costs you something that is not money: your data held hostage, an export that does not work, ads inside your invoice, or a "free" tier so narrow it is a demo with a login screen.

The line here is drawn differently. Export works on the free plan — CSV, Excel and JSON — because data you cannot get out is not data you own. The invoice is a real compliant invoice, not a sample. The limits are on volume and on the conveniences, not on whether the thing works.

Start free now. If it does not suit you, take your data with you.

Reliability, backups and getting your data out

Cloud billing software is only as good as its worst day. Two things matter more than any feature list: that your data is backed up somewhere you can reach, and that you can export it in a format something else can read.

Exports here are CSV, Excel and JSON, on every plan including the free one, covering customers, products, invoices and payments. That is the honest test of whether software respects you — not what it promises, but what it lets you take when you leave.

Frequently asked questions

When do I have to issue a self-invoice?

Where you receive a supply attracting reverse charge from an unregistered supplier, there is no supplier invoice, so you raise one yourself for that inward supply in its own series. Which supplies attract reverse charge has been changed by notification, so confirm the current position.

Is a VAT invoice still valid in India?

VAT was replaced by GST in July 2017, so for an Indian supply today the document is a GST tax invoice. VAT is still live in other countries, which is usually why the term comes up — if you are exporting, that obligation belongs to the buyer's jurisdiction, not on your invoice.

Can I issue one invoice for a whole day of small sales?

For small-value supplies to unregistered customers below a prescribed amount, where no invoice was asked for, a consolidated invoice for the day is permitted. It does not extend to B2B supplies, which are reported invoice by invoice because the customer's credit depends on the detail.

Is my data shared with anyone?

No. It sits in this installation, scoped to your company. AI requests only happen when you explicitly ask for one, and nothing is sent anywhere otherwise.

Is it really free?

Yes. The Free plan is ₹0, needs no card and has no expiry. It has volume limits and leaves out the paid conveniences — watermark-free PDFs, GST return exports, the AI features, extra logins — but the invoices it produces are real GST invoices, and you can export your data from it whenever you like.

Start free, decide later

You do not have to choose a plan to begin. Start on Free, use it for as long as it suits you, and upgrade only when a limit actually gets in your way — never automatically, and never because a countdown ran out.

Open the software demo → — or create the free account from the same page.

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