The Cronos POS chain is the base layer of the Cronos ecosystem. It is a Cosmos SDK blockchain that runs on Tendermint proof of stake, and it is the chain that issues the CRO token. A set of validators, capped at the top 100 by stake, secures it.
Everything else in Cronos leans on it. CRO is minted here and staked here, so this chain both creates the token and keeps it secure. It is a Cosmos-style chain, not the app chain most people picture, and it was first launched as the Crypto.org Chain. Its main job is fast, low-cost payments.
Most guides blur it into a single thing called Cronos, but it helps to see the POS chain as the distinct base layer sitting underneath everything else.
How the Cronos POS chain is built
The Cronos POS chain is built with the Cosmos SDK and runs on Tendermint Core, a proof-of-stake consensus engine. Validators take turns proposing and confirming blocks, and once enough of them agree, a block is final almost at once. That instant settlement is what makes the chain quick and cheap to use.
The Cosmos SDK is a toolkit for building blockchains, and Tendermint Core is the engine that lets validators agree on the order of transactions (source: Cronos POS Chain Docs). Together they give the chain Byzantine fault tolerant consensus, which keeps working even if some validators fail or act dishonestly.
Two kinds of computer run it. Validator nodes propose and confirm blocks, while full nodes keep a copy of the history for apps and wallets. Because Tendermint finalizes a block as soon as enough validators sign it, there is no long wait and no mining race. For the general idea behind staking-based security, the base primer on proof of work and proof of stake covers the mechanics this chain relies on.
Why it is called the layer zero, and the home of CRO
Cronos calls the POS chain its layer zero because it secures the wider ecosystem and issues CRO, the token every Cronos chain runs on. In other words, this is where CRO is born and where its security starts. The chain was built for real-world payments and for NFTs, not for hosting complex apps.
Layer zero is Cronos's own label for the base chain, and it points to two jobs. The first is security: the value staked on the POS chain backs the ecosystem's trust. The second is issuance: this is the chain that mints CRO, the single token that pays fees and secures every Cronos chain (source: Cronos POS, EVM & zkEVM FAQ).
That is a different role from the Cronos EVM chain, where the DeFi apps and games live. The POS chain is closer to a mint and a settlement layer than a busy app store. It grew out of Crypto.org Pay, which is why its design leans toward fast, cheap transfers and NFTs rather than heavy smart contracts. For the overview of how the token and chains fit together, see the hub on what Cronos is.
The validators that secure the chain
The Cronos POS chain is run by validators, and its active set is capped at the top 100 by the amount of CRO staked to them. Anyone can help without running a validator by delegating CRO to one, which is how the chain shares out both the work of securing it and the rewards that come from doing so.
Validators are the computers that keep the chain running, and staking is how they earn the right to do it. Unlike proof of work, where miners compete by burning electricity, a Cronos POS validator puts CRO at stake as a bond for honest behavior (source: Cronos POS Chain Technical Glossary). The more CRO staked to a validator, the more likely it is to sit in the active set.
You do not need your own validator. By delegating CRO to one, you lend it your stake and share the rewards it earns after commission, while your coins stay yours. The trade-off is that a validator which misbehaves can be penalized, and delegators share that loss, so the choice matters. The rewards, lock-up, and slashing risk have their own guide in staking CRO; here the point is that staking secures the chain.
How on-chain governance works
The Cronos POS chain is governed on-chain, which means CRO holders steer it by voting rather than a company deciding alone. Staked CRO is the vote. Anyone can submit a proposal with a deposit, and stakers then vote yes, no, no with veto, or abstain, with the result written into the chain's own rules.
On-chain governance means the rules can change through a vote recorded on the blockchain itself, not in a boardroom. A proposal starts with a deposit, which discourages spam, then moves into a voting period (source: Cronos POS Chain Module Overview). Your voting power is the amount of CRO you have staked.
There is a shortcut worth knowing. If you delegate and do not vote, your stake follows that validator's vote by default, and casting your own vote overrides it for your share. Proposals can change network settings, fund work from a community pool, or approve upgrades, so governance is how the chain evolves rather than sitting frozen. Holding and staking CRO comes with a small say in how it is run.
How it connects to the wider Cosmos world through IBC
Because it is a Cosmos chain, the Cronos POS chain can talk to other blockchains through IBC, the Inter-Blockchain Communication protocol. IBC lets separate chains pass tokens and messages to each other under shared rules, so CRO and other assets can move between the POS chain, the Cronos EVM chain, and the wider Cosmos network.
IBC is what makes the POS chain part of a bigger network rather than an island. It is a shared standard that lets independent Cosmos chains move tokens and data between each other without a custodian (source: Coinbase). It also supports interchain accounts, which let one chain act on another.
In practice, CRO can start on the POS chain and end up usable elsewhere: stake it here, then move some to the Cronos EVM chain for a DeFi app, with the token keeping its value at each step. IBC handles movement between Cosmos chains, while separate bridges connect Cronos to outside networks like Ethereum, which is why matching the network on both ends of any transfer matters.
How the POS chain fits with the other Cronos chains
The Cronos POS chain is one of two active chains today. It issues and secures CRO, while the Cronos EVM chain runs the apps, and a third chain, the zkEVM, is being retired. The POS chain is not affected by that wind-down, so it stays the base layer beneath the whole ecosystem.
Here is how the active chains and the retiring one line up:
| Chain | What it does | Consensus | Status |
|---|---|---|---|
| Cronos POS | Issues and secures CRO, payments, NFTs | Open proof of stake, on Tendermint | Active |
| Cronos EVM | Runs DeFi apps, games, and NFTs | Proof of authority | Active, main focus |
| Cronos zkEVM | An Ethereum layer-2, now retiring | Ethereum, via zero-knowledge proofs | Winding down, shuts June 2027 |
The zkEVM is the only chain in that table on its way out. Cronos Labs decided to consolidate its effort onto the Cronos EVM chain, and the zkEVM Alpha is set to shut down for good on June 3, 2027 (source: Cronos Labs). None of that touches the POS chain, which keeps issuing and securing CRO as before.
From BloFin's operational view, most people meet CRO as a traded position long before they ever touch the Cronos POS chain directly, since on BloFin CRO trades as a USDT-margined perpetual rather than as native coins held on the chain. That is worth stating plainly: you can take a view on CRO without running a validator, staking, or moving anything on-chain. For how the chains connect, the guide to how Cronos works puts the POS chain back in context.
Frequently asked questions
Why does a Cronos POS address look different from a Cronos EVM address?
Cronos POS uses its own address format, commonly starting with cro, while Cronos EVM uses Ethereum-style 0x addresses. The same wallet application can control both, but they are different destinations on different networks. Copying an address from a wallet screen does not tell an exchange which network you intended. Select the withdrawal network first, then compare the full destination address and send a small test amount when a route is new.
What should I inspect before delegating CRO to a validator?
Look beyond the displayed reward rate. Check the validator's commission, uptime and missed-block record, public operator information, and how much voting power it already has. The aim is not to find a guaranteed best validator, but to understand the operator and terms you are choosing. Read the wallet's current status information before you confirm, and revisit it periodically. Delegation is a network-security choice with trade-offs, not a savings account with a fixed return.
What happens if I redelegate CRO to a different validator?
Redelegating moves your delegated stake from one validator to another without treating it as a sale or a bridge transfer. It is not a way to switch operators repeatedly at no cost, though. Cronos POS applies a redelegation cooldown to limit rapid hopping between validators. Before confirming, check the new validator's status and the current cooldown shown by your wallet or the official documentation. Do not assume a redelegation fixes a separate network or custody mistake.
Why might my staked CRO not appear in a Cronos EVM app?
A wallet can use one recovery phrase for several chains while still keeping each chain's balances separate. A Cronos EVM app reads the EVM network, so it does not automatically display CRO delegated on Cronos POS. That absence does not mean the stake vanished or should be bridged. Open the wallet's Cronos POS view, or use its matching explorer, to check the delegation record before taking any action. Treat a shared wallet interface as a convenience, not proof of one merged balance.
Can I stake CRO with a hardware wallet?
Possibly, if the hardware wallet and the wallet software you use both support Cronos POS staking. The important part is that the device shows the native Cronos POS address and the exact delegation transaction before you approve it. A hardware wallet protects the signing key, but it cannot make a wrong validator, network, or transaction harmless. Confirm compatibility from the wallet vendor's current documentation, keep the device firmware updated, and read the device screen before signing.
What records should I keep after sending CRO from an exchange?
Save the exchange withdrawal confirmation, transaction hash, selected network, destination address, time, and amount. Those details make it possible to trace a transfer in an explorer and give a support team the information it needs if a balance does not appear. A screenshot alone is weaker than the on-chain transaction hash, because it may omit the final routing details. Keep the records until the destination balance and transaction status both match what you expected.
Researched and written by the BloFin Academy editorial team with AI-assisted drafting. Updated July 2026. Primary sources: the Cronos POS chain documentation, the crypto-org-chain project on GitHub, and the Cronos Labs blog. All facts independently verified against cited documentation current as of July 2026.
This article is educational and general in nature, not financial or investment advice. Cryptocurrencies like CRO carry real risks, including price volatility, validator slashing, lock-up and unbonding periods, governance changes, smart-contract bugs, and the chance of losing funds sent on the wrong network. Nothing here is a recommendation to buy, sell, stake, or hold any asset. Do your own research, and consider a licensed professional before making financial decisions. BloFin does not provide investment advice.