V1 Deployed Endpoints, Message Libraries, and Relayer

LayerZero V1 is deprecated. This page is provided for reference and legacy integrations only. For new projects, please use LayerZero V2.

Below you can find a description of the main LayerZero V1 contracts and find the corresponding deployment information for each blockchain network LayerZero V1 supports.

Endpoint Id values have no relation to Chain Id values. Since LayerZero spans both EVM and non-EVM chains, each Endpoint contract has a unique identifier known as the endpointId for determining which chain’s endpoint to send to or receive messages from.When using LayerZero V1 contract methods, be sure to use the correct endpointId listed below:

1xx: refer to mainnet chains
10xxx: refer to testnet chains

Contract Description

Contract Name	Description
EndpointV1	The primary entrypoint into LayerZero V1 responsible for managing crosschain communications. It orchestrates message sending and receiving between various smart contract connections.
UltraLightNodeV2	The Ultra Light Node (ULN) message library contract responsible for verifying and validating crosschain messages using oracle and relayer attestations.
RelayerV2	A contract responsible for relaying crosschain messages. The relayer picks up messages from the source chain and delivers them to the destination chain’s endpoint.
NonceContract	Tracks message nonces to ensure proper message ordering and prevent replay attacks across chains.
SendUln301	A send message library contract for LayerZero V1 that handles outbound message preparation and validation.
ReceiveUln301	A receive message library contract for LayerZero V1 that handles inbound message verification and delivery.

Sepolia Testnet Endpoint

The Sepolia testnet endpoint is connected to Ethereum, Arbitrum, and Optimism mainnets only.

Property	Value
EndpointId	`161`
Endpoint	`0x7cacBe439EaD55fa1c22790330b12835c6884a91`
RelayerV2	`0x306B9a8953B9462F8b826e6768a93C8EA7454965`
ULNV2	`0x41Bdb4aa4A63a5b2Efc531858d3118392B1A1C3d`
NonceContract	`0xc097ab8CD7b053326DFe9fB3E3a31a0CCe3B526f`

Checking Default Configs

To see the default configuration for a given pathway (i.e., from Chain A to Chain B), you can use LayerZero Scan’s Default Checker.

⌘I

​Contract Description

​Sepolia Testnet Endpoint

​Checking Default Configs

Contract Description

Sepolia Testnet Endpoint

Checking Default Configs