diff --git a/.changeset/rare-items-deliver.md b/.changeset/rare-items-deliver.md
new file mode 100644
index 0000000000..dab2a43986
--- /dev/null
+++ b/.changeset/rare-items-deliver.md
@@ -0,0 +1,5 @@
+---
+"viem": patch
+---
+
+Add Swellchain
diff --git a/src/chains/definitions/swellchain.ts b/src/chains/definitions/swellchain.ts
new file mode 100644
index 0000000000..71c778cb73
--- /dev/null
+++ b/src/chains/definitions/swellchain.ts
@@ -0,0 +1,28 @@
+import { chainConfig } from '../../op-stack/chainConfig.js'
+import { defineChain } from '../../utils/chain/defineChain.js'
+
+export const swellchain = /*#__PURE__*/ defineChain({
+  ...chainConfig,
+  id: 1923,
+  name: 'Swellchain',
+  nativeCurrency: { name: 'Ether', symbol: 'ETH', decimals: 18 },
+  rpcUrls: {
+    default: {
+      http: ['https://swell-mainnet.alt.technology', 'https://rpc.ankr.com/swell'],
+    },
+  },
+  blockExplorers: {
+    default: {
+      name: 'Swell Explorer',
+      url: 'https://explorer.swellnetwork.io',
+      apiUrl: 'https://explorer.swellnetwork.io/api',
+    },
+  },
+  contracts: {
+    ...chainConfig.contracts,
+    multicall3: {
+      address: '0xcA11bde05977b3631167028862bE2a173976CA11',
+      blockCreated: 1,
+    },
+  },
+})
diff --git a/src/chains/index.ts b/src/chains/index.ts
index ed22b26140..7525d08644 100644
--- a/src/chains/index.ts
+++ b/src/chains/index.ts
@@ -431,6 +431,7 @@ export { superseedSepolia } from './definitions/superseedSepolia.js'
 export { swan } from './definitions/swan.js'
 export { swanProximaTestnet } from './definitions/swanProximaTestnet.js'
 export { swanSaturnTestnet } from './definitions/swanSaturnTestnet.js'
+export { swellchain } from './definitions/swellchain.js'
 export { swissdlt } from './definitions/swissdlt.js'
 export { syscoin } from './definitions/syscoin.js'
 export { syscoinTestnet } from './definitions/syscoinTestnet.js'