BNB Smart Chain: Jenner hardfork

Jenner is a BNB Smart Chain (BSC) hardfork that activates on Mainnet on December 8, 2026, at 02:30 UTC (Unix timestamp 1796697000). It activated on BNB Smart Chain Testnet (Chapel) on October 29, 2026. Jenner includes three BSC-only BNB Evolution Proposals (BEPs), listed in BEP-718:

BEP	Change	What it means for you
BEP-702	Compliant asset standard (CAS20), a token standard built into the protocol as stateful precompiles	A new kind of token at reserved addresses. Token creation opens separately, through a governance-controlled switch
BEP-703	Payment lane: 5% of each block’s gas reserved for payment transactions	General transactions can never use more than 95% of a block’s gas at the default ratio, even when the lane is empty
BEP-706	Millisecond block timestamp precompile at `0x70`	Contracts can read block time in milliseconds; `block.timestamp` stays in seconds

Jenner also charges the double-sign evidence precompile at 0x68 per input byte. The BSC client release that schedules the fork, v1.8.2, also carries RPC changes that apply as soon as a node upgrades, before activation. See RPC changes that ship with the client upgrade.

Chainstack BNB Smart Chain Global Nodes serve requests at recent blocks with BSC client v1.8.2, the release that schedules Jenner on Mainnet.

Millisecond block timestamp precompile (BEP-706)

After activation, a precompiled contract at 0x0000000000000000000000000000000000000070 returns the executing block’s timestamp in milliseconds. It closes a gap left by faster blocks: BSC blocks now come faster than once a second, so several blocks can share one block.timestamp value.

Input: none. The precompile ignores calldata.
Output: a 32-byte big-endian unsigned integer, the block time in milliseconds since the Unix epoch.
Gas: 20.
block.timestamp and the TIMESTAMP opcode are unchanged and still return seconds.

The value is the same one block headers have carried since the Lorentz hardfork: the header timestamp in seconds plus the millisecond remainder stored in mixHash. The precompile makes it readable from a contract:

Solidity

function milliTimestamp() internal view returns (uint64) {
    (bool ok, bytes memory data) = address(0x70).staticcall("");
    require(ok, "milliTimestamp: call failed");
    return uint64(uint256(bytes32(data)));
}

Before activation, 0x70 holds no code and an eth_call to it returns 0x. You can preview the precompile before activation with an eth_call that overrides the block time to a moment after it:

cURL

curl -X POST YOUR_CHAINSTACK_ENDPOINT \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","id":1,"method":"eth_call","params":[{"to":"0x0000000000000000000000000000000000000070","data":"0x"},"latest",null,{"time":"0x6b176be4"}]}'

Response

{"jsonrpc":"2.0","id":1,"result":"0x000000000000000000000000000000000000000000000000000001a2537d72a0"}

0x1a2537d72a0 is 1796697060000 milliseconds, the overridden time 0x6b176be4 (1796697060 seconds) times 1,000. The millisecond part is zero because overriding only time resets the millisecond remainder.

Payment lane (BEP-703)

From the block after activation, every block reserves a share of its gas, 5% by default, that general transactions cannot use. The reservation is an accounting rule, not a separate region of the block: payment and general transactions stay interleaved and ordered by fee as before. A transaction counts as a payment when it is not a system transaction, has a to address, has type 0x00, 0x01, or 0x02, and one of these holds:

to is on the payment contract list that BSC governance maintains. The list starts empty after the fork; stablecoins such as USDT and USDC are the intended first entries.
It sends a non-zero BNB value to an account that holds no code. An account with an EIP-7702 delegation counts as holding code.

Everything else, including any transaction to a contract that is not on the list, is a general transaction. Each block must satisfy:

generalGasUsed + max(paymentGasUsed, paymentLaneQuota) <= gasLimit
paymentLaneQuota = gasLimit × ratio / 10000      # ratio defaults to 500, capped at 1000

At the current Mainnet block gas limit of 70,000,000, the quota is 3,500,000 gas. When payment transactions use less than the quota, general transactions are limited to the rest, 66,500,000 gas. When payment demand meets or exceeds the quota, payment and general transactions compete for the remaining space on equal fee terms. Governance can change the ratio, up to 10%, and the payment contract list through the PaymentLane system contract at 0x0000000000000000000000000000000000002007. A change takes effect from the block after the one that carries it.

Compliant asset standard: CAS20 (BEP-702)

CAS20 is a fungible token standard implemented in the node as stateful precompiled contracts rather than as deployed bytecode. Tokens have compliance controls built in: shared allowlists and blocklists, transfer policies, pausing, a supply cap, and separate roles for minting, burning, and seizure.

Contract	Address
CAS20Factory	`0xCA5F000000000000000000000000000000000000`
ActivationRegistry	`0x7020000000000000000000000000000000000001`
PolicyRegistry	`0x7020000000000000000000000000000000000002`

Token addresses are derived deterministically and start with 0xCA52. A token account holds a one-byte sentinel instead of executable code. The hardfork puts the CAS20 code on every node, but token creation stays closed until an administrator appointed by BSC governance opens it through the ActivationRegistry. Existing BEP-20 tokens are unaffected.

RPC changes that ship with the client upgrade

These changes come with the BSC client upgrade, not with Jenner activation. The tracer, eth_simulateV1, and eth_getStorageValues changes arrived in v1.8.0-alpha, and the prevRandao check in v1.8.1. Chainstack BNB Smart Chain Global Nodes apply them to requests at recent blocks.

Tracer output follows the Geth format

debug_trace* calls that return opcode-level structLogs changed format in v1.8.0-alpha, a breaking change for parsers written against the previous output:

memory words are 0x-prefixed and padded to 32 bytes.
storage keys and values are 0x-prefixed.
error is omitted from a step when it is empty.

The tracing config no longer includes reexec. Requests that still pass it succeed. A debug_traceCall with {"enableMemory": true} on v1.8.2 returns steps like:

{
  "memory": [
    "0x0000000000000000000000000000000000000000000000000000000000000000",
    "0x0000000000000000000000000000000000000000000000000000000000000000"
  ],
  "storage": {
    "0x0000000000000000000000000000000000000000000000000000000000000003": "0x00000000000000000000000000000000000000001dada59ce83bb9a18098fbc1"
  }
}

`prevRandao` overrides must be a millisecond remainder

In eth_call, eth_estimateGas, debug_traceCall, and eth_simulateV1, a blockOverrides.prevRandao value must encode a millisecond remainder from 0 to 999 as a 32-byte hex value. Any larger value fails:

{"jsonrpc":"2.0","id":1,"error":{"code":-32000,"message":"block override \"prevRandao\" on BSC must be less than 1000, got 1000"}}

blockOverrides.time stays in seconds. Overriding only time sets the millisecond remainder to zero.

`eth_simulateV1` reports peak gas

Each call result from eth_simulateV1 now has a maxUsedGas field next to gasUsed. gasUsed has gas refunds deducted; maxUsedGas is the most gas the call consumed during execution, before refunds.

New method: `eth_getStorageValues`

eth_getStorageValues reads up to 1,024 storage slots, across one or more contracts, in a single call. On BNB Smart Chain Global Nodes, it serves the latest 128 blocks; use eth_getStorageAt for older state.

Additional resources

BEP-718: Hardfork Meta-Jenner
BSC client release notes for the RPC changes: v1.8.2, v1.8.1, and v1.8.0-alpha
BNB Smart Chain methods
BNB Smart Chain: Lorentz hardfork

Last modified on November 12, 2026

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BNB Smart Chain: Jenner hardfork

Millisecond block timestamp precompile (BEP-706)

Payment lane (BEP-703)

Compliant asset standard: CAS20 (BEP-702)

RPC changes that ship with the client upgrade

Tracer output follows the Geth format

`prevRandao` overrides must be a millisecond remainder

`eth_simulateV1` reports peak gas

New method: `eth_getStorageValues`

Additional resources

​Millisecond block timestamp precompile (BEP-706)

​Payment lane (BEP-703)

​Compliant asset standard: CAS20 (BEP-702)

​RPC changes that ship with the client upgrade

​Tracer output follows the Geth format

​prevRandao overrides must be a millisecond remainder

​eth_simulateV1 reports peak gas

​New method: eth_getStorageValues

​Additional resources

Millisecond block timestamp precompile (BEP-706)

Payment lane (BEP-703)

Compliant asset standard: CAS20 (BEP-702)

RPC changes that ship with the client upgrade

Tracer output follows the Geth format

`prevRandao` overrides must be a millisecond remainder

`eth_simulateV1` reports peak gas

New method: `eth_getStorageValues`

Additional resources