diff --git a/.changeset/pretty-clubs-press.md b/.changeset/pretty-clubs-press.md
new file mode 100644
index 000000000..204fc8616
--- /dev/null
+++ b/.changeset/pretty-clubs-press.md
@@ -0,0 +1,5 @@
+---
+'@solana/errors': minor
+---
+
+Mark the `cause` deprecated for `SOLANA_ERROR__INSTRUCTION_PLANS__FAILED_TO_EXECUTE_TRANSACTION_PLAN` error
diff --git a/packages/errors/src/__typetests__/error-typetest.ts b/packages/errors/src/__typetests__/error-typetest.ts
index 7773e6dfa..e80c372ab 100644
--- a/packages/errors/src/__typetests__/error-typetest.ts
+++ b/packages/errors/src/__typetests__/error-typetest.ts
@@ -1,7 +1,7 @@
 import * as SolanaErrorCodeModule from '../codes';
 import { SolanaErrorCode, SolanaErrorCodeWithCause } from '../codes';
 import { SolanaErrorContext } from '../context';
-import { isSolanaError, SolanaError } from '../error';
+import { isSolanaError, SolanaError, SolanaErrorWithDeprecatedCause } from '../error';
 
 const { SOLANA_ERROR__TRANSACTION__FEE_PAYER_SIGNATURE_MISSING, SOLANA_ERROR__TRANSACTION__SIGNATURES_MISSING } =
     SolanaErrorCodeModule;
@@ -66,3 +66,19 @@ null as unknown as SolanaErrorContext satisfies {
 // Special errors have a nested `cause` property that is an optional `SolanaError`
 const errorWithCause = null as unknown as SolanaError<SolanaErrorCodeWithCause>;
 errorWithCause.cause satisfies SolanaError | undefined;
+
+// Errors that have a deprecated `cause` property should satisfy `SolanaErrorWithDeprecatedCause`
+// when narrowed with `isSolanaError`
+{
+    const e = null as unknown;
+    if (isSolanaError(e)) {
+        // @ts-expect-error Not all SolanaErrors have deprecated cause
+        e satisfies SolanaErrorWithDeprecatedCause;
+    }
+    // This one does
+    if (isSolanaError(e, SolanaErrorCodeModule.SOLANA_ERROR__INSTRUCTION_PLANS__FAILED_TO_EXECUTE_TRANSACTION_PLAN)) {
+        e satisfies SolanaErrorWithDeprecatedCause;
+        // context still works
+        e.context.transactionPlanResult satisfies unknown;
+    }
+}
diff --git a/packages/errors/src/codes.ts b/packages/errors/src/codes.ts
index fc686d2c5..2e102622b 100644
--- a/packages/errors/src/codes.ts
+++ b/packages/errors/src/codes.ts
@@ -624,3 +624,10 @@ export type SolanaErrorCode =
  * `cause`.
  */
 export type SolanaErrorCodeWithCause = typeof SOLANA_ERROR__JSON_RPC__SERVER_ERROR_SEND_TRANSACTION_PREFLIGHT_FAILURE;
+
+/**
+ * Errors of this type have a deprecated `cause` property. Consumers should use the error's
+ * `context` instead to access relevant error information.
+ */
+export type SolanaErrorCodeWithDeprecatedCause =
+    typeof SOLANA_ERROR__INSTRUCTION_PLANS__FAILED_TO_EXECUTE_TRANSACTION_PLAN;
diff --git a/packages/errors/src/error.ts b/packages/errors/src/error.ts
index f7a4ef2d5..f169cc610 100644
--- a/packages/errors/src/error.ts
+++ b/packages/errors/src/error.ts
@@ -1,7 +1,24 @@
-import { SolanaErrorCode, SolanaErrorCodeWithCause } from './codes';
+import { SolanaErrorCode, SolanaErrorCodeWithCause, SolanaErrorCodeWithDeprecatedCause } from './codes';
 import { SolanaErrorContext } from './context';
 import { getErrorMessage } from './message-formatter';
 
+/**
+ * A variant of {@link SolanaError} where the `cause` property is deprecated.
+ *
+ * This type is returned by {@link isSolanaError} when checking for error codes in
+ * {@link SolanaErrorCodeWithDeprecatedCause}. Accessing `cause` on these errors will show
+ * a deprecation warning in IDEs that support JSDoc `@deprecated` tags.
+ */
+export interface SolanaErrorWithDeprecatedCause<
+    TErrorCode extends SolanaErrorCodeWithDeprecatedCause = SolanaErrorCodeWithDeprecatedCause,
+> extends Omit<SolanaError<TErrorCode>, 'cause'> {
+    /**
+     * @deprecated The `cause` property is deprecated for this error code.
+     * Use the error's `context` property instead to access relevant error information.
+     */
+    readonly cause?: unknown;
+}
+
 /**
  * A type guard that returns `true` if the input is a {@link SolanaError}, optionally with a
  * particular error code.
@@ -44,6 +61,14 @@ import { getErrorMessage } from './message-formatter';
  * }
  * ```
  */
+export function isSolanaError<TErrorCode extends SolanaErrorCodeWithDeprecatedCause>(
+    e: unknown,
+    code: TErrorCode,
+): e is SolanaErrorWithDeprecatedCause<TErrorCode>;
+export function isSolanaError<TErrorCode extends SolanaErrorCode>(
+    e: unknown,
+    code?: TErrorCode,
+): e is SolanaError<TErrorCode>;
 export function isSolanaError<TErrorCode extends SolanaErrorCode>(
     e: unknown,
     /**
diff --git a/packages/errors/src/messages.ts b/packages/errors/src/messages.ts
index c1b3f4274..f0168ba13 100644
--- a/packages/errors/src/messages.ts
+++ b/packages/errors/src/messages.ts
@@ -433,7 +433,7 @@ export const SolanaErrorMessages: Readonly<{
     [SOLANA_ERROR__INSTRUCTION_PLANS__NON_DIVISIBLE_TRANSACTION_PLANS_NOT_SUPPORTED]:
         'This transaction plan executor does not support non-divisible sequential plans. To support them, you may create your own executor such that multi-transaction atomicity is preserved — e.g. by targetting RPCs that support transaction bundles.',
     [SOLANA_ERROR__INSTRUCTION_PLANS__FAILED_TO_EXECUTE_TRANSACTION_PLAN]:
-        'The provided transaction plan failed to execute. See the `transactionPlanResult` attribute and the `cause` error for more details.',
+        'The provided transaction plan failed to execute. See the `transactionPlanResult` attribute for more details. Note that the `cause` property is deprecated, and a future version will not set it.',
     [SOLANA_ERROR__INSTRUCTION_PLANS__MESSAGE_CANNOT_ACCOMMODATE_PLAN]:
         'The provided message has insufficient capacity to accommodate the next instruction(s) in this plan. Expected at least $numBytesRequired free byte(s), got $numFreeBytes byte(s).',
     [SOLANA_ERROR__INVARIANT_VIOLATION__INVALID_TRANSACTION_PLAN_KIND]: 'Invalid transaction plan kind: $kind.',