diff --git a/CHANGELOG.md b/CHANGELOG.md
index 1d74720baf..8c8987f344 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -55,6 +55,7 @@ The minor version will be incremented upon a breaking change and the patch versi
 - ts: Remove `base64-js` dependency ([#2635](https://github.com/coral-xyz/anchor/pull/2635)).
 - syn: `IdlTypeDefinitionTy` enum has a new variant `Alias` ([#2637](https://github.com/coral-xyz/anchor/pull/2637)).
 - cli, client, lang, spl: Solana `1.14` is no longer supported, minimum required Solana version is `1.16.0` ([#2645](https://github.com/coral-xyz/anchor/pull/2645)).
+- ts: Change Provider.publicKey type into `PublicKey | null` instead of `PublicKey | undefined`, `AccountClient.createInstruction(signer: Signer, size?: number)` into `AccountClient.createInstruction(signerPubkey: PublicKey, size?: number)` ([#2665](https://github.com/coral-xyz/anchor/issues/2665)).
 
 ## [0.28.0] - 2023-06-09
 
diff --git a/ts/packages/anchor/package.json b/ts/packages/anchor/package.json
index e5bbd40df6..15a65f598f 100644
--- a/ts/packages/anchor/package.json
+++ b/ts/packages/anchor/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@coral-xyz/anchor",
-  "version": "0.28.1-beta.2",
+  "version": "0.28.1-beta.3",
   "description": "Anchor client",
   "module": "./dist/esm/index.js",
   "main": "./dist/cjs/index.js",
diff --git a/ts/packages/anchor/src/program/namespace/account.ts b/ts/packages/anchor/src/program/namespace/account.ts
index e5e6731743..f8c5800c59 100644
--- a/ts/packages/anchor/src/program/namespace/account.ts
+++ b/ts/packages/anchor/src/program/namespace/account.ts
@@ -349,12 +349,12 @@ export class AccountClient<
    * Returns an instruction for creating this account.
    */
   async createInstruction(
-    signer: Signer,
+    signerPubkey: PublicKey,
     sizeOverride?: number
   ): Promise<TransactionInstruction> {
-    const size = this.size;
+    const size = sizeOverride ?? this.size;
 
-    if (this._provider.publicKey === undefined) {
+    if (!this._provider.publicKey) {
       throw new Error(
         "This function requires the Provider interface implementor to have a 'publicKey' field."
       );
@@ -362,12 +362,10 @@ export class AccountClient<
 
     return SystemProgram.createAccount({
       fromPubkey: this._provider.publicKey,
-      newAccountPubkey: signer.publicKey,
-      space: sizeOverride ?? size,
+      newAccountPubkey: signerPubkey,
+      space: size,
       lamports:
-        await this._provider.connection.getMinimumBalanceForRentExemption(
-          sizeOverride ?? size
-        ),
+        await this._provider.connection.getMinimumBalanceForRentExemption(size),
       programId: this._programId,
     });
   }
diff --git a/ts/packages/anchor/src/provider.ts b/ts/packages/anchor/src/provider.ts
index 02affbe0e1..e41fdd663e 100644
--- a/ts/packages/anchor/src/provider.ts
+++ b/ts/packages/anchor/src/provider.ts
@@ -21,7 +21,7 @@ import {
 
 export default interface Provider {
   readonly connection: Connection;
-  readonly publicKey?: PublicKey;
+  readonly publicKey: PublicKey | null;
 
   send?(
     tx: Transaction | VersionedTransaction,