If you run EV chargers across more than one site, the version of OCPP your hardware speaks isn't a technical footnote — it quietly decides what you can monitor, how secure your network is, and how much smart-charging headroom you have. And right now most operators are running a mix of versions whether they planned to or not.
Here's the practical version of what's changed between OCPP 1.6 and 2.0.1, why it matters for day-to-day operations, and what to actually do about it.
The 30-second version
| OCPP 1.6 | OCPP 2.0.1 | OCPP 2.1 | |
|---|---|---|---|
| Status | ~90% of deployed chargers | <10%, growing | Newest, early adoption |
| Security | Basic; no native TLS | WSS/TLS, 3 security profiles | Builds on 2.0.1 |
| Smart charging | Static profiles | Dynamic, EMS + ISO 15118 input | Bidirectional / V2G focus |
| Device management | Limited | Built-in diagnostics, monitoring | Extended |
| Backward compatible? | — | No — full redesign | Aligns with 2.0.1 |
The headline: 2.0.1 is not an upgrade you flip on. It's a redesigned protocol. It dropped SOAP, restructured messaging, and is not backward compatible with 1.6. That single fact shapes every decision below.
Why this matters now
Roughly 90% of OCPP-compatible chargers in the field still run version 1.6. Less than 10% run 2.0.1. So the real world isn't "1.6 _or_ 2.0.1" — it's both, often on the same network, often at the same site.
That means the version question isn't "which one should I buy?" It's "can my management software run a mixed fleet without forcing me to standardize on one?" If your CSMS only speaks one version cleanly, every hardware decision you make for the next five years gets narrower.
What actually changed
1. Security got serious. OCPP 1.6 predates a lot of the threat awareness the industry now takes for granted. It lacks native transport security, which is a growing liability for any operator processing payments or managing access control. OCPP 2.0.1 made security a core design goal: WebSocket Secure (WSS), TLS encryption, and three defined security profiles covering charger and CSMS authentication. If you're handling public paid charging, this is the difference that matters most.
2. Smart charging went from static to dynamic. In 1.6, charging profiles are essentially fixed — they can't react to real-time conditions. 2.0.1 accepts direct input from Energy Management Systems and supports ISO 15118, so charging can flex with on-site load, demand charges, and grid signals. For multifamily and fleet operators trying to avoid expensive electrical upgrades, that's the feature that pays for itself.
3. Device management is built in. 2.0.1 added native diagnostics, monitoring, and firmware-update handling. Less time guessing why a charger went dark; more of that visibility comes through the protocol itself instead of vendor workarounds.
4. Data got leaner. Transaction handling was consolidated into a single TransactionEvent message, and WebSocket compression reduces data overhead — useful at scale and on cellular-connected chargers.
So should you wait for 2.0.1 hardware?
No. Two reasons.
First, 1.6 isn't obsolete — it runs the overwhelming majority of working chargers today and will for years. Ripping it out to chase 2.0.1 is rarely justified.
Second, you don't control your own timeline anyway. You'll add chargers from different manufacturers, inherit sites running older firmware, and gradually mix 2.0.1 in as new hardware lands. The winning move isn't picking a version — it's refusing to get locked into one.
What operators should actually do
- Run the mixed fleet on purpose. Assume you'll have 1.6 and 2.0.1 (and eventually 2.1) side by side. Plan for it instead of fighting it.
- Choose a CSMS that speaks all three. If your management platform handles 1.6, 2.0.1, and 2.1 natively, version becomes a non-issue — you buy the best hardware for each site and the software sorts it out.
- Prioritize 2.0.1 where security and load management matter most. Public paid charging and load-constrained sites get the most value from the upgrade.
- Don't re-platform to change versions. If switching OCPP versions means switching software, your software is the problem.
FAQ
Is OCPP 1.6 still safe to use? For private and access-controlled charging, yes — it's the industry workhorse. For public paid charging, prioritize the stronger transport security in 2.0.1.
Can OCPP 1.6 and 2.0.1 chargers run on the same platform? They should. A capable CSMS manages both concurrently. If yours can't, that's a limitation of the software, not the protocol.
Do I need to upgrade my chargers to 2.0.1? Not as a blanket move. Upgrade where security or dynamic smart charging justify it; otherwise keep healthy 1.6 hardware running.
_WAI EV runs OCPP 1.6, 2.0.1, and 2.1 on one console — so you can manage a mixed fleet across every site without re-platforming or vendor lock-in._ See how it works →