diff --git a/src/api/exchange/_methods/reserveRequestWeight.ts b/src/api/exchange/_methods/reserveRequestWeight.ts
index 55f990fd..c1aa0c93 100644
--- a/src/api/exchange/_methods/reserveRequestWeight.ts
+++ b/src/api/exchange/_methods/reserveRequestWeight.ts
@@ -4,7 +4,7 @@ import * as v from "@valibot/valibot";
 // API Schemas
 // ============================================================
 
-import { Hex, UnsignedInteger } from "../../_schemas.ts";
+import { Address, Hex, UnsignedInteger } from "../../_schemas.ts";
 
 /**
  * Reserve additional rate-limited actions for a fee.
@@ -18,6 +18,8 @@ export const ReserveRequestWeightRequest = /* @__PURE__ */ (() => {
       type: v.literal("reserveRequestWeight"),
       /** Amount of request weight to reserve. */
       weight: v.pipe(UnsignedInteger, v.maxValue(1844674407370955)), // Truncated max uint64 / 1000
+      /** Address of an existing user to reserve the weight for. */
+      destination: v.optional(Address),
     }),
     /** Nonce (timestamp in ms) used to prevent replay attacks. */
     nonce: UnsignedInteger,
diff --git a/tests/api/exchange/reserveRequestWeight.test.ts b/tests/api/exchange/reserveRequestWeight.test.ts
index 7df820bd..7bf7810b 100644
--- a/tests/api/exchange/reserveRequestWeight.test.ts
+++ b/tests/api/exchange/reserveRequestWeight.test.ts
@@ -15,7 +15,10 @@ runTest({
   name: "reserveRequestWeight",
   codeTestFn: async (_t, exchClient) => {
     const params: ReserveRequestWeightParameters[] = [
+      // no destination
       { weight: 1 },
+      // destination
+      { weight: 1, destination: "0xe019d6167e7e324aed003d94098496b6d986ab05" },
     ];
 
     const data = await Promise.all(params.map((p) => exchClient.reserveRequestWeight(p)));