What an ERP is and when an SME needs one

> Declaration of interest: BAI Business offers a business management platform and publishes this article. It is signed by Héctor Redondo, CEO and founder of BAI Business.

Today I want to talk about what an ERP is, that word you hear in meetings and almost everyone nods along to without knowing exactly what it means.

An ERP (enterprise resource planning) is the software where a company handles everything to do with money and day-to-day operations: invoices, purchases, stock, expenses, sometimes accounting and the team. It is the inside of the business. If the CRM looks outwards, at your customers, the ERP looks inwards, at your numbers and your inventory.

What it usually contains

It depends on the software, but a typical ERP brings together:

• Sales and invoicing: quotes, invoices, payments.
• Purchasing and suppliers: orders, expenses, what you owe.
• Stock: what you have, what has been sold, what needs restocking.
• Accounting or preparing for it: income, expenses, monthly summary.
• Team: schedules, clocking in, sometimes payroll.

The idea is that everything sits in one place so data is not copied from one program to another.

How many companies use one

According to Spain's National Statistics Institute (INE), 63.6% of companies in Spain with 10 or more employees and an internet connection use ERP software (survey on ICT use in companies, first quarter of 2025, accessed on 11 October 2026). That is far more than the 34.5% who use a CRM in the same report. My reading: companies start by organising money and stock, and leave organising customers for later.

This figure is for companies with 10 or more employees; for those with fewer than 10, that INE release does not measure ERP.

When an SME needs one

Imagine a business with a shop and a small warehouse that sells in the store, on WhatsApp and in an online shop. Every sale has to subtract stock in all three places; otherwise, one day it sells something it no longer has. If it also invoices by hand and writes expenses in a notebook, the quarter arrives and it spends a whole afternoon sorting papers. (An invented example to explain the idea, not a real customer.)

You start to need an ERP, or something like it, when:

• You sell through more than one channel and the stock stops adding up.
• You invoice with different tools and put everything together by hand at the end of the quarter.
• Your team clocks in, signs or gets paid and you track that separately.
• You cannot say, without doing the sums, how much comes in and goes out this month.

When you do not need a big one

Here is an honest opinion: the classic ERP sounds like a big-company tool and a months-long implementation project, and for an SME it is often too much. If you invoice, keep an eye on a bit of stock and look after your team, you do not need to plan a factory. You need those things working together, simple, and at a price that does not cost you sleep. And if what you do is plan production, an industrial ERP is what you need and BAI is not that.

What we have built at BAI

BAI's platform does what someone asking for an ERP in an SME is looking for: customers, invoices, stock and team in one place, switched on module by module, set up with you by our team. I use BAI's product catalogue every day: you add each product once and it appears on your website, on social media and in your WhatsApp catalogue, and each sale subtracts stock. Invoices come out of the customer record, numbered, with a QR code and registered with Verifactu, and payments come with a reminder and a payment link. You do not have to take all the modules: you start with what is most urgent and add the rest without changing system.

That is why I gave you the criteria first and my own product after.

What to do now

Write down three things this week: where you record your invoices, where you record your expenses and where you check your stock. If they are three different places and you put them together by hand, you have your answer.

If you want to see how we do it, it is in BAI's management platform. And if you wonder how it differs from a CRM, see CRM or ERP: differences and which one your SME needs.

How we checked this

I read the INE figures directly in its press release (ICT use table by region, total row) on 11 October 2026. What I say about BAI comes from the published pages of our website. I wrote it with the help of artificial intelligence from the cited sources and from what we use at BAI; I sign it myself.

Sources

• INE, "Encuesta sobre el uso de TIC y del comercio electrónico en las empresas. Año 2024 - Primer trimestre 2025": https://www.ine.es/dyngs/Prensa/ETICCE20241T2025.htm (accessed on 11 October 2026). Percentages over companies with 10 or more employees and an internet connection.
• Description of BAI's platform: published page the management platform.