Comparison
MES vs ERP: what each does, and when you need both
ERP plans and accounts for the business: orders, materials, purchasing, stock and cost. MES runs and records production on the shop floor: which order is on which machine, what was made, what was scrapped, which batch went into which product. ERP works in days and transactions; MES works in minutes and events. Most growing plants need both, connected.
Understand
MES and ERP side by side
| ERP | MES | |
|---|---|---|
| Main job | Plan and account for the business | Execute and record production |
| Time scale | Days, weeks, periods | Seconds to shifts |
| Users | Finance, purchasing, sales, planning | Operators, supervisors, quality, maintenance |
| Typical data | Sales orders, BOMs, stock, costs, invoices | Machine states, counts, WIP, genealogy, defects |
| ISA 95 level | Level 4 | Level 3 |
| Examples | SAP S/4HANA, Oracle, Microsoft Dynamics, Tally | SAP Digital Manufacturing, Siemens Opcenter, DELMIA Apriso, custom MES |
What ERP production modules do not cover
- Live machine status, downtime and OEE.
- Enforcing the routing and quality checks at each step on the floor.
- Detailed genealogy: which batch of component went into which serial or batch of product.
- Operator instructions and sign offs at the line.
- Sequencing and dispatching within a shift in response to what actually happens.
How it works
Signs you need an MES alongside ERP
- ERP confirmations are typed in a day later, so stock and order status are always behind.
- You cannot say why a shift missed its target until someone investigates.
- A customer complaint takes days to trace back to batch and machine.
- Quality checks live on paper and are hard to audit.
- Scrap in ERP is lower than scrap on the floor.
How MES and ERP connect
ERP releases production orders with BOMs and routings to the MES. The MES executes them, capturing machine and operator data, and sends back confirmations, material consumption, output, scrap and quality results. Master data such as materials and routings is owned by ERP; execution data is owned by MES. Deciding this ownership early prevents most integration problems.
Work with us
How we help
We implement MES functions alongside your ERP, packaged or custom, and build the integration to SAP, Oracle, Microsoft Dynamics, Tally or a custom ERP. If ERP plus simple tracking is enough for your plant today, we will tell you.
What we have built
Our RFID and QR based vendor material system syncs with SAP in real time, covering vendor materials worth more than ₹20,000 crore (about US$2.4 billion) moved every day.
Figures are company reported from past projects. They are not independently audited benchmarks and are not a promise for another plant. Read the case studies.
Frequently asked questions
Can ERP replace MES?
For simple, low volume production, ERP with basic production recording can be enough. As volumes, product variety, quality requirements or traceability needs grow, ERP alone does not give real time execution control, which is what an MES adds.
Which comes first, ERP or MES?
Usually ERP, because orders, materials and finance need a system of record first. MES is added when shop floor visibility, traceability or execution control becomes the constraint.
Does SAP include an MES?
SAP offers SAP Digital Manufacturing as a separate MES product. SAP ERP production planning records production but is not an MES by itself.
Is MES the same as MRP?
No. MRP, material requirements planning, is a planning function inside ERP that calculates what to buy and make. MES executes and records production on the floor.
Related reading
References
Start with one line and one number
We scope one line, agree the number that should move, and show it moving before anything is scaled. You keep the code and the data.
Step 1
An engineer reads it
Not a sales bot. Our team replies within 24 hours with questions or times for a call.
Step 2
30 minute call
Your process, machines, systems and the number you want to move. We tell you honestly if we are a fit.
Step 3
A written scope for one line
What we would connect, what you would see, how long it takes. You decide; nothing starts without your approval.
Reviewed by Amey Kadle, Founder, Ajinkya Technologies. Last reviewed: .