How do the OCPP versions differ?
In the operations centre, the night shift hands over. Two thirds of the network still runs OCPP 1.6, the newer chargers 2.0.1.
Next year's tender asks for OCPP 2.1.
The questionWhat separates the versions, and why do operators run them side by side?
| Released | IEC standard | Highlights | |
|---|---|---|---|
| OCPP 1.6maintenance mode, no further changes | 2015 | smart charging | |
| OCPP 2.0.1not backward compatible with 1.6 | 2020 | IEC 63584 | security, device model |
| OCPP 2.1compatible with 2.0.1 | 2025 | IEC 63584-210 | bidirectional, DER |
Release years and standardisation from the Open Charge Alliance. OCPP 1.6 will no longer evolve.
Why 2.0.1 broke with 1.6
2.0.1 is not an incremental extension of 1.6; it is not backward compatible. Two changes made the break necessary:
- Transactions. Start and end of a transaction became configurable, all transaction data moved into one message type, and the charger, not the backend, now creates the transaction ID.
- . A new way to describe, configure and monitor every component of a charger, welcomed by operators of mixed networks.
OCPP 2.1 builds on 2.0.1 and keeps it compatible.
Same roles, new names
OCPP 1.6 speaks of the Charge Point and the ; from OCPP 2.0.1 on, they are the charging station and the charging station management system, CSMS, and OCPP 2.1 keeps these names. The roles stay the same. This site uses the industry term CPMS, charge point management system, for the backend in every version.
| 1.6 | 2.0.1 | 2.1 | |
|---|---|---|---|
| Ad hoc paymentcard or contactless | custom | OCA custom | native |
| Price displaybefore charging | OCA custom | native | native |
| Smart charginglimits and profiles | native | native | native |
| Bidirectionalenergy back to the grid | native |
Native: in the specification; OCA custom: through a customisation published by the Open Charge Alliance. From the OCA white paper on AFIR.
Check your understanding
3 questions. Answer all of them to complete this stop. Each answer explains itself.
Why is OCPP 2.0.1 not backward compatible with 1.6?
Configurable transactions, a single transaction message and the device model required a clean break.
Which version supports bidirectional charging natively?
OCPP 2.1 added functional blocks for bidirectional energy flows and distributed energy resources.
What is IEC 63584?
OCPP 2.0.1 was published as IEC 63584 in 2024, OCPP 2.1 as IEC 63584-210.
- OCPP Open Charge Point Protocol: the open protocol between a charger and its operator's backend. EV charging fundamentals, stop 03 Glossary
- CPMS Charge point management system: the operator's software backend that monitors and controls the chargers. OCPP calls it the Central System in version 1.6 and the CSMS, charging station management system, from version 2.0.1 on. EV charging fundamentals, stop 02 Glossary
- Device model OCPP 2.0.1's standard description of a charger's components and variables, for configuration and monitoring across manufacturers. Stop 06 Glossary
- Open Charge Alliance: Open Charge Point Protocol (OCPP): versions 1.6, 2.0.1 and 2.1. https://openchargealliance.org/protocols/open-charge-point-protocol/. Checked 09 Oct 2026.
- Open Charge Alliance: Introduction to OCPP (presentation, April 2026). https://openchargealliance.org/wp-content/uploads/2026/04/Introduction-to-OCPP.pdf. Checked 09 Oct 2026. Licence: CC BY-ND 4.0.
- Open Charge Alliance: What is new in OCPP 2.0.1? Whitepaper, version 1.0, March 2023. https://openchargealliance.org/wp-content/uploads/2024/01/new_in_ocpp_201-v10.pdf. Checked 09 Oct 2026. Licence: CC BY-ND 4.0.
- Open Charge Alliance: What is new in OCPP 2.0.1? Whitepaper, version 1.0, March 2023. https://openchargealliance.org/wp-content/uploads/2024/01/new_in_ocpp_201-v10.pdf. Checked 09 Oct 2026. Licence: CC BY-ND 4.0.
- Open Charge Alliance: What is new in OCPP 2.0.1? Whitepaper, version 1.0, March 2023. https://openchargealliance.org/wp-content/uploads/2024/01/new_in_ocpp_201-v10.pdf. Checked 09 Oct 2026. Licence: CC BY-ND 4.0.
- Open Charge Alliance: Open Charge Point Protocol (OCPP): versions 1.6, 2.0.1 and 2.1. https://openchargealliance.org/protocols/open-charge-point-protocol/. Checked 09 Oct 2026.
- Open Charge Alliance: OCPP 1.6 Security Whitepaper, edition 4, February 2026. https://openchargealliance.org/ocpp-info-whitepapers/ocpp-1-6-security-whitepaper-4th-edition/. Checked 09 Oct 2026. Licence: CC BY-ND 4.0.
- Open Charge Alliance: What is new in OCPP 2.0.1? Whitepaper, version 1.0, March 2023. https://openchargealliance.org/wp-content/uploads/2024/01/new_in_ocpp_201-v10.pdf. Checked 09 Oct 2026. Licence: CC BY-ND 4.0.
- Open Charge Alliance: AFIR and OCPP, white paper v1.0, January 2024. https://openchargealliance.org/wp-content/uploads/2025/05/ocpp_and_afir-white-paper.pdf. Checked 09 Oct 2026. Licence: CC BY-ND 4.0.