---
id: "invoice-numbering"
lang: "en"
title: "Invoice numbering"
summary: "Choose how invoice numbers look: a prefix, which can carry the date, then a running number. New sales use the new format; old invoices keep theirs."
area: "Settings & account"
kind: "task"
url: "https://zeropos.shop/help/invoice-numbering"
alternate: "https://zeropos.shop/help/invoice-numbering?lang=es"
markdown: "https://zeropos.shop/help/md/en/invoice-numbering.md"
screens: ["/backoffice/settings/invoicing"]
where_to_find: ["MANAGE › Settings › Invoice numbering"]
related: ["find-an-invoice","receipts-and-printing","company-info","locations"]
updated: "2026-10-16"
---

# Invoice numbering

Choose how invoice numbers look: a prefix, which can carry the date, then a running number. New sales use the new format; old invoices keep theirs.

A number is the prefix, the separator and a counter padded with zeros, such as INV202609-000001. The standard format starts the counter again each month, because the month is in the prefix. A workspace created in Spanish starts with FAC instead of INV.

Where to find it: MANAGE › Settings › Invoice numbering.

## Before you start

- Changing it needs the permission to edit invoicing settings: owners and administrators by default. Managers can read it.
- If your country has rules for invoice numbers, check with your accountant first.

## Steps

1. Open [MANAGE › Settings › Invoice numbering](https://app.zeropos.shop/backoffice/settings/invoicing).
2. Under **Format**, write the **Prefix template**. {YYYY}, {YY}, {MM} and {DD} become the year, month or day of the sale, on your shop's clock ([Company info: name, time zone and tax](https://zeropos.shop/help/company-info)).
3. Set the **Separator**, up to 3 characters, and the **Padding width**: how many digits the counter has, from 1 to 12.
4. Check the **Live preview**, then tap **Save**.

## What happens next

- The next sale gets a number in the new format; invoices already made keep their numbers.
- When the prefix changes, the counter carries on from the highest number that already uses that prefix, or starts at 1.

## When the counter starts again

The counter starts again at 1 whenever the prefix itself changes. With {MM} in it, that happens every month; with {YYYY} alone, every January; with no date at all, never.

The date changes at midnight on the shop's clock, the time zone in [MANAGE › Settings › Company info](https://app.zeropos.shop/backoffice/settings/company): a sale at 00:30 on the 1st is numbered in the new month, as its receipt is dated.

So the prefix is the whole rule: to start again every year, keep {YYYY} and take out {MM}.

## The preview

The **Live preview** shows the shape of the numbers with today's date on the shop's clock, as a sale made now gets it, counting from 1. The real next number carries on from the last one.

## One format, and {LOC}

Every sale, at every till, is numbered in this one format. Refunds have numbers of their own.

{LOC} prints a shop's **Short code**, set in the shop's form under [MANAGE › Locations](https://app.zeropos.shop/backoffice/locations), and only when **Include location code.** is ticked. A shop with no code prints nothing there.

## Common questions

### Can I change the format in the middle of the year?

Yes. Old invoices keep their numbers and new ones use the new format. For a clean break, change it at the start of a month or a year.

### Can I change the number of an invoice already made?

No. Numbers are given when the sale is made and stay with it. See [Find an invoice](https://zeropos.shop/help/find-an-invoice) to look one up.

### Can I have a separate series for proformas?

No. Every sale is numbered in the one format on this screen.

## Good to know

- Keep the year in the prefix, such as INV{YYYY}: numbers stay short and never clash from one year to the next.

## Related guides

- [Find an invoice](https://zeropos.shop/help/md/en/find-an-invoice.md)
- [Design the receipt](https://zeropos.shop/help/md/en/receipts-and-printing.md)
- [Company info: name, time zone and tax](https://zeropos.shop/help/md/en/company-info.md)
- [Add a shop or storage location](https://zeropos.shop/help/md/en/locations.md)