diff --git a/web3.js/module.d.ts b/web3.js/module.d.ts
index 65b53f7e2f..63e3eed9bf 100644
--- a/web3.js/module.d.ts
+++ b/web3.js/module.d.ts
@@ -180,7 +180,7 @@ declare module '@solana/web3.js' {
     ): Promise<RpcResponseAndContext<number>>;
     getBalance(publicKey: PublicKey, commitment?: Commitment): Promise<number>;
     getClusterNodes(): Promise<Array<ContactInfo>>;
-    getConfirmedBlock(): Promise<ConfirmedBlock>;
+    getConfirmedBlock(slot: number): Promise<ConfirmedBlock>;
     getVoteAccounts(commitment?: Commitment): Promise<VoteAccountStatus>;
     confirmTransactionAndContext(
       signature: TransactionSignature,
diff --git a/web3.js/module.flow.js b/web3.js/module.flow.js
index 27adc8a493..9f1400eb43 100644
--- a/web3.js/module.flow.js
+++ b/web3.js/module.flow.js
@@ -193,7 +193,7 @@ declare module '@solana/web3.js' {
     ): Promise<RpcResponseAndContext<number>>;
     getBalance(publicKey: PublicKey, commitment: ?Commitment): Promise<number>;
     getClusterNodes(): Promise<Array<ContactInfo>>;
-    getConfirmedBlock(): Promise<ConfirmedBlock>;
+    getConfirmedBlock(slot: number): Promise<ConfirmedBlock>;
     getVoteAccounts(commitment: ?Commitment): Promise<VoteAccountStatus>;
     confirmTransactionAndContext(
       signature: TransactionSignature,