diff --git a/package.json b/package.json
index ba3fa0d94..0d99dcf2c 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "opensea-js",
-  "version": "7.1.10",
+  "version": "7.1.11",
   "description": "TypeScript SDK for the OpenSea marketplace helps developers build new experiences using NFTs and our marketplace data",
   "license": "MIT",
   "author": "OpenSea Developers",
diff --git a/src/types.ts b/src/types.ts
index def5c070e..ec574c7ef 100644
--- a/src/types.ts
+++ b/src/types.ts
@@ -123,6 +123,8 @@ export enum Chain {
   Solana = "solana",
   /** Zora */
   Zora = "zora",
+  /** Sei */
+  Sei = "sei",
 
   // Testnet Chains
   // ⚠️NOTE: When adding to this list, also add to the util function `isTestChain`
@@ -148,6 +150,8 @@ export enum Chain {
   SolanaDevnet = "soldev",
   /** Zora Sepolia */
   ZoraSepolia = "zora_sepolia",
+  /** Sei Testnet */
+  SeiTestnet = "sei_testnet",
 }
 
 /**
diff --git a/src/utils/utils.ts b/src/utils/utils.ts
index d3111ea13..642d2b116 100644
--- a/src/utils/utils.ts
+++ b/src/utils/utils.ts
@@ -212,6 +212,10 @@ export const getChainId = (chain: Chain) => {
       return "7777777";
     case Chain.ZoraSepolia:
       return "999999999";
+    case Chain.Sei:
+      return "1329";
+    case Chain.SeiTestnet:
+      return "1328";
     default:
       throw new Error(`Unknown chainId for ${chain}`);
   }
@@ -257,6 +261,10 @@ export const getWETHAddress = (chain: Chain) => {
     case Chain.Zora:
     case Chain.ZoraSepolia:
       return "0x4200000000000000000000000000000000000006";
+    case Chain.Sei:
+      return "0xe30fedd158a2e3b13e9badaeabafc5516e95e8c7";
+    case Chain.SeiTestnet:
+      return "0x3921ea6cf927be80211bb57f19830700285b0ada";
     default:
       throw new Error(`Unknown WETH address for ${chain}`);
   }
@@ -321,6 +329,7 @@ export const isTestChain = (chain: Chain): boolean => {
     case Chain.OptimismSepolia:
     case Chain.SolanaDevnet:
     case Chain.ZoraSepolia:
+    case Chain.SeiTestnet:
       return true;
     default:
       return false;