Invoice numbering for SMEs and self-employed

Invoice numbering for SMEs and self-employed: difference between serie or prefix and invoice number. How to create an invoice numbering sequence .

Invoice numbering

Invoice numbers inside each series should be assigned sequentially without containing repeats or gaps and in chronological order.

Invoice number

The sequential number of your invoice is built with only numbers. These numbers must be consecutive inside the same serie or sequence.

Invoice sequence: How to create a new serie with a prefix

The sequence or serie of an invoice is the part of your invoice number which is used to differentiate your business lines. The serie or prefix is also used to differentiate invoices from corrective invoices.

How to create invoice numbering sequences with prefixes

You can custom your invoice prefixes with numbers and letters as you wish. Each customized prefix will create a new invoice serie.

Below you can see an example made with Contasimple:

Invoice numbering for freelancers and SMEs

Next to your new invoice, the series "Normal invoices" will appear by default.

You can create and configure your invoice series in a personalized way, set the one you want to use by default, and create as many other invoice series as you need for your business.

To get started, click "Create new series".

Create new numbering series

Then it will appear this box, where you can give a name to your new series, and configure its numbering easily:

Set new numbering series

Example: since in our business we have several establishments, we have decided that we will create an invoice numbering sequence for each one of them. In the example, we have created an invoicing series that we have named "London", because we have an establishment in this city.

In the "Mask" box, we have configured the numbering of our new series so that the invoices created in our London establishment always start with "LO", followed by the year, and four figures that are to be automatically filled in with the corresponding numbers, starting with 0001.

This is what the number of the first invoice of this new series will look like:

Example of new numbering series

How to set up your invoice series

If you click on "Configure series", this box will open the list of all the series of invoices that you have created yourself, and the two that already come by default in Contasimple:

Set a numbering series as default

As you can see, the new invoice sequence of invoices "London" is already in the list. If you click on the star, this invoice sequence will become the one that will always appear by default when you issue a new invoice. You can also edit it to modify its numbering, deactivate it and delete it. From here you can also create new invoice sequence of invoices.

Mandatory invoice series: The corrective invoice

There are some cases in which creating invoice numbering sequences is mandatory. The most common is the corrective invoice.

The Contasimple series of corrective invoices consists, by default, of creating a new series starting with "R" for "Rectifying". Then comes a hyphen, followed by the corrective invoice number. But you can also configure this series to customize it if you want.

In this link we tell you how the series of corrective invoice.

Bill your customers from the Contasimple Billing App

Contasimple's App is designed to make your daily tasks even easier.

  • Create invoices, delivery notes and register your tickets.

  • Check your schedule of customers and suppliers.

  • View all your virtual disk documents.

  • Certified digitization of invoices.

  • Time tracking also from the app.

Available for Android and iOS. Totally free!

App to make free invoices

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Contasimple is the online invoicing and accounting program that allows you to save money and time to grow your business.

Register now and you will have 30 free days of the Ultimate Plan, the most complete.
Then you can move to the free Basic Plan for life.

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Create your invoices in 10 seconds, personalize them with your logo and send them to your costumers.

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Create your budgets in 10 seconds. Convert it on an invoice in just 1 click.

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Delivery notes

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Everything you need to comply with the law and understand your business.

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Electronic signature

Upload your certificate and sign any kind of document, invoice, delivery note or estimate.

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Virtual disk

Upload your private documents and link them with your invoices or delivery notes.

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Control of expenses

Tracking and controlling expenses had never been so easy.

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Customer Management

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Stock control

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Time tracking

Keep track of your employee's worked hours.

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Generate receipts and bank remittances to charge your customers.

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Dropbox & Google Drive

We integrate with Dropbox and Google Drive. Each created invoice will be automatically uploaded to your account.

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With our module of reports, in a single click you can obtain the most relevant data of the state of your business.

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Global vision

With our Dashboard you will have a global vision to support the decision making of your business.
Get to know your internal processes thoroughly.

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Export in PDF and Excel all your invoices, movements, accounts, clients, ...

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Manage your individual notes.


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