A CRM manages your customer relationships from first contact to quote; an ERP system handles orders, stock, purchasing and accounting. People speak of the front office and the back office: the CRM wins customers, the ERP fulfils the order. Which you need first depends on where your business is currently stuck.
What is the difference between CRM and ERP?
The table compares the two systems.
| Criterion | CRM | ERP |
|---|---|---|
| Area | Front office: sales, marketing, customer contact | Back office: fulfilment, stock, purchasing, finance |
| Key question | Who is interested in us, and how far has the conversation got? | What was ordered, delivered and paid? |
| Core data | Contacts, enquiries, conversations, quotes, status | Articles, stock, orders, invoices, payments |
| Typical users | Sales, management, customer service | Warehouse, purchasing, accounting, production |
| Result | More deals closed, fewer forgotten enquiries | Fewer errors, current stock and figures |
The two systems overlap on customer master data, quotes and invoices. So the name does not decide; the question is where you lose the most time and make the most errors.
Which should you start with?
Ask yourself where it hurts most. If enquiries get lost, quotes are not followed up and you do not know how many prospects are in conversation, start with a CRM. If stock levels are wrong, orders are entered twice or month-end closing takes days, you need an inventory system or ERP more.
For most service businesses, a CRM with invoicing software is a good start. Traders with stock often begin with inventory management and add a CRM later. A decision guide for the CRM is in When is a CRM worth it for a small business?, and an explanation of the other system in What is an ERP system?.
Some providers sell both as a package. That can be convenient but creates dependence. Check whether you can export data and replace individual parts later.
How do the two systems work together?
As soon as both are in use, double work arises if you transfer data by hand from one system to the other. Interfaces solve this: when a quote is accepted in the CRM, the system automatically creates an order in the ERP. When the invoice is paid there, sales sees it in the CRM. Technically, such connections usually use an API, an interface through which programs talk to each other. More in What is an API?.
A clear rule on which system leads for which data matters. Customer master data, for example, is maintained only in the CRM and stock levels only in the ERP. Without this rule you eventually have two different addresses in the system and nobody knows which is right.
What does the combination cost?
Costs depend on the scope of the systems and the interfaces. At WebDrift, business systems start at €3,900 plus €149 a month for hosting and support; the price depends on scope and connections. All prices are final prices under § 19 UStG. Also plan time for data migration and training, because it can cost more than the software itself.
- Pain points written down: lost enquiries, stock errors, double entry
- Decided whether to improve sales or fulfilment first
- Defined which system leads for which data
- Interfaces between the systems clarified
- Time planned for data migration and training
- Started with one system and reviewed the results
Conclusion: solve the biggest pain first
CRM and ERP complement each other, and neither has to do everything at once. Solve first the problem that costs you the most time or customers, and connect the systems once both are running. If you want help with the order, describe your process.




