diff --git a/src/lib/components/payload/payload-code-block.svelte b/src/lib/components/payload/payload-code-block.svelte
index 65b8a17ca4..4fe7c3147e 100644
--- a/src/lib/components/payload/payload-code-block.svelte
+++ b/src/lib/components/payload/payload-code-block.svelte
@@ -1,34 +1,109 @@
 <script lang="ts">
+  import Button from '$lib/holocene/button.svelte';
   import CodeBlock from '$lib/holocene/code-block.svelte';
+  import Icon from '$lib/holocene/icon/icon.svelte';
   import { translate } from '$lib/i18n/translate';
-  import type {
-    PayloadContainingObject,
-    PotentiallyDecodable,
+  import {
+    downloadExternalPayloadWithCodec,
+    NO_CODEC_SERVER_CONFIGURED_ERROR,
+  } from '$lib/services/data-encoder';
+  import { toaster } from '$lib/stores/toaster';
+  import type { Payload, Payloads } from '$lib/types';
+  import {
+    isExternallyStoredRawPayload,
+    isRawPayload,
+    parseRawPayloadToJSON,
+    type PayloadContainingObject,
   } from '$lib/utilities/decode-payload';
+  import { formatBytes } from '$lib/utilities/format-bytes';
+  import { isNetworkError } from '$lib/utilities/is-network-error';
+  import { stringifyWithBigInt } from '$lib/utilities/parse-with-big-int';
 
   import PayloadDecoder from './payload-decoder.svelte';
 
   interface Props {
-    value: PotentiallyDecodable | PayloadContainingObject;
+    value: Payload | Payloads | PayloadContainingObject;
     maxHeight?: number;
     testId?: string;
   }
 
   let { value, maxHeight, testId }: Props = $props();
+
+  let downloadError: string | undefined = $state(undefined);
+
+  const downloadExternalPayload = async (payload: Payload) => {
+    let data: Payloads | undefined = undefined;
+    try {
+      data = await downloadExternalPayloadWithCodec(payload);
+      const parsed = parseRawPayloadToJSON(data.payloads[0], false);
+      const content = stringifyWithBigInt(parsed);
+      const a = document.createElement('a');
+      const file = new Blob([content], { type: 'json/plain' });
+      a.href = URL.createObjectURL(file);
+      a.download = 'payload.json';
+      a.click();
+    } catch (error) {
+      console.error(error);
+      if (isNetworkError(error) && error.statusCode === 404) {
+        downloadError = 'Unable to download payload file.';
+        toaster.push({
+          variant: 'error',
+          duration: 5000,
+          message:
+            'Unable to download file due to codec server not having a /download endpoint configured. Update codec server and try again.',
+        });
+      } else if (error === NO_CODEC_SERVER_CONFIGURED_ERROR) {
+        downloadError =
+          'Unable to download payload file. No codec server is configured.';
+        toaster.push({
+          variant: 'error',
+          duration: 5000,
+          message:
+            'Unable to download file due to no codec server being configured. Add a codec server with a /download endpoint and try again.',
+        });
+      }
+    }
+  };
 </script>
 
 <PayloadDecoder {value}>
-  {#snippet children(decodedValue)}
+  {#snippet children(results)}
     <div class="space-y-2">
-      {#each decodedValue as data (data)}
-        <CodeBlock
-          content={data}
-          {maxHeight}
-          copyIconTitle={translate('common.copy-icon-title')}
-          copySuccessIconTitle={translate('common.copy-success-icon-title')}
-          {testId}
-          language="json"
-        />
+      {#each results as result (result.decodedValue)}
+        {#if isExternallyStoredRawPayload(result.decodedValue)}
+          <CodeBlock
+            content={stringifyWithBigInt(result.decodedValue.data)}
+            {maxHeight}
+            copyIconTitle={translate('common.copy-icon-title')}
+            copySuccessIconTitle={translate('common.copy-success-icon-title')}
+            {testId}
+            language="json"
+          >
+            {#snippet headerActions()}
+              <Button
+                size="sm"
+                variant="ghost"
+                leadingIcon="download"
+                on:click={() => downloadExternalPayload(result.originalValue)}
+              >
+                {formatBytes(
+                  result.decodedValue.externalPayloads?.[0].sizeBytes,
+                )}
+              </Button>
+            {/snippet}
+          </CodeBlock>
+          {#if downloadError}
+            <div class="flex items-center gap-1 text-danger">
+              <Icon name="exclamation-octagon" />
+              <p>{downloadError}</p>
+            </div>
+          {/if}
+          <p>
+            Payload downloads require a codec server with a <span
+              class="rounded-sm bg-code-block px-1 font-mono">/download</span
+            > endpoint.
+          </p>
+        {/if}
       {/each}
     </div>
   {/snippet}
diff --git a/src/lib/components/payload/payload-decoder.svelte b/src/lib/components/payload/payload-decoder.svelte
index 7a4382249a..68af83c37a 100644
--- a/src/lib/components/payload/payload-decoder.svelte
+++ b/src/lib/components/payload/payload-decoder.svelte
@@ -1,52 +1,102 @@
+<script lang="ts" module>
+  export type DecodedPayloadResult = {
+    decodedValue: ParsedPayload | PayloadContainingObject;
+    originalValue: Payload | PayloadContainingObject;
+  }[];
+</script>
+
 <script lang="ts">
   import { type Snippet } from 'svelte';
 
+  import type { Payload, Payloads } from '$lib/types';
   import {
     decodeEventAttributes,
     decodePayloadAndParseDataToJSON,
     decodePayloadsAndParseDataToJSON,
     isRawPayload,
     isRawPayloads,
+    type ParsedPayload,
     type PayloadContainingObject,
-    type PotentiallyDecodable,
   } from '$lib/utilities/decode-payload';
-  import { stringifyWithBigInt } from '$lib/utilities/parse-with-big-int';
 
-  export const decodePayloadValue = async (
-    value: PotentiallyDecodable | PayloadContainingObject,
-  ): Promise<string[]> => {
+  type T = $$Generic<PayloadContainingObject>;
+
+  const decodePayloadValue = async (
+    value: Payload,
+  ): Promise<DecodedPayloadResult> => {
+    const decodedPayload = await decodePayloadAndParseDataToJSON(value, false);
+    const result = [
+      {
+        decodedValue: decodedPayload,
+        originalValue: value,
+      },
+    ];
+
+    onDecode?.(result);
+    return result;
+  };
+
+  const decodePayloadsValue = async (
+    value: Payloads,
+  ): Promise<DecodedPayloadResult> => {
+    const decodedPayloads = await decodePayloadsAndParseDataToJSON(
+      value,
+      false,
+    );
+    const result = decodedPayloads.map((decodedPayload, idx) => {
+      return {
+        decodedValue: decodedPayload,
+        originalValue: value.payloads[idx],
+      };
+    });
+
+    onDecode?.(result);
+    return result;
+  };
+
+  const decodePayloadContainingObjectValue = async <
+    T extends PayloadContainingObject,
+  >(
+    value: T,
+  ): Promise<DecodedPayloadResult> => {
+    const decodedValue = await decodeEventAttributes(value);
+    const result = [
+      {
+        decodedValue,
+        originalValue: value,
+      },
+    ];
+
+    onDecode?.(result);
+    return result;
+  };
+
+  const decodeValue = (
+    value: Payload | Payloads | T,
+  ): Promise<DecodedPayloadResult> => {
     if (isRawPayload(value)) {
-      const decodedPayloadData = await decodePayloadAndParseDataToJSON(value);
-      const stringified = stringifyWithBigInt(decodedPayloadData);
-      onDecode?.([stringified]);
-      return [stringified];
-    } else if (isRawPayloads(value)) {
-      const parsedPayloadsData = await decodePayloadsAndParseDataToJSON(value);
-      const stringified = parsedPayloadsData.map((data) =>
-        stringifyWithBigInt(data),
-      );
-      onDecode?.(stringified);
-      return stringified;
-    } else {
-      const decoded = await decodeEventAttributes(value);
-      const stringified = stringifyWithBigInt(decoded);
-      onDecode?.([stringified]);
-      return [stringified];
+      return decodePayloadValue(value);
     }
+
+    if (isRawPayloads(value)) {
+      return decodePayloadsValue(value);
+    }
+
+    return decodePayloadContainingObjectValue(value);
   };
 
-  interface Props {
-    value: PotentiallyDecodable | PayloadContainingObject;
-    onDecode?: (decodedPayloads: string[]) => void;
-    children: Snippet<[decodedPayloads: string[]]>;
-    loading?: Snippet;
-  }
+  type Props = {
+    value: Payload | Payloads | T;
+    children: Snippet<[DecodedPayloadResult]>;
+    onDecode?: (result: DecodedPayloadResult) => void;
+    loading?: Snippet<[]>;
+  };
 
-  let { value, onDecode, children, loading }: Props = $props();
+  let { value, children, onDecode, loading }: Props = $props();
 </script>
 
-{#await decodePayloadValue(value)}
+{#await decodeValue(value)}
   {@render loading?.()}
-{:then decodedValue}
-  {@render children(decodedValue)}
+{:then decodeResult}
+  {@render children(decodeResult)}
 {/await}
diff --git a/src/lib/components/payload/payload-inline.svelte b/src/lib/components/payload/payload-inline.svelte
index a7ae23fffc..7b769b6def 100644
--- a/src/lib/components/payload/payload-inline.svelte
+++ b/src/lib/components/payload/payload-inline.svelte
@@ -1,5 +1,6 @@
 <script lang="ts">
   import type { PotentiallyDecodable } from '$lib/utilities/decode-payload';
+  import { stringifyWithBigInt } from '$lib/utilities/parse-with-big-int';
 
   import PayloadDecoder from './payload-decoder.svelte';
 
@@ -13,12 +14,13 @@
 </script>
 
 <PayloadDecoder {value}>
-  {#snippet children(decodedValue)}
+  {#snippet children(result)}
+    {@const stringifiedData = stringifyWithBigInt(result[0].decodedValue.data)}
     <div
       class="overflow-hidden border border-subtle bg-code-block px-1 py-0.5 font-mono text-xs text-primary {className}"
     >
       <code>
-        <pre class="truncate">{decodedValue.slice(0, truncateAt)}</pre>
+        <pre class="truncate">{stringifiedData.slice(0, truncateAt)}</pre>
       </code>
     </div>
   {/snippet}
diff --git a/src/lib/components/schedule/schedule-form/schedule-input-payload.svelte b/src/lib/components/schedule/schedule-form/schedule-input-payload.svelte
index cbda4c872c..a44c4b1caa 100644
--- a/src/lib/components/schedule/schedule-form/schedule-input-payload.svelte
+++ b/src/lib/components/schedule/schedule-form/schedule-input-payload.svelte
@@ -1,7 +1,9 @@
 <script lang="ts">
   import type { Writable } from 'svelte/store';
 
-  import PayloadDecoder from '$lib/components/payload/payload-decoder.svelte';
+  import PayloadDecoder, {
+    type DecodedPayloadResult,
+  } from '$lib/components/payload/payload-decoder.svelte';
   import PayloadInputWithEncoding from '$lib/components/payload-input-with-encoding.svelte';
   import Button from '$lib/holocene/button.svelte';
   import { translate } from '$lib/i18n/translate';
@@ -35,8 +37,9 @@
   let initialMessageType = $state('');
   let loading = $state(true);
 
-  const setInitialInput = (decodedValue: string[]): void => {
-    initialInput = decodedValue[0];
+  const setInitialInput = (result: DecodedPayloadResult): void => {
+    initialInput = result[0].decodedValue.data;
+
     input = initialInput;
     let currentEncoding: PayloadInputEncoding = 'json/plain';
     let currentMessageType = '';
diff --git a/src/lib/holocene/code-block.svelte b/src/lib/holocene/code-block.svelte
index 1cce013ce3..a31b8a287a 100644
--- a/src/lib/holocene/code-block.svelte
+++ b/src/lib/holocene/code-block.svelte
@@ -295,7 +295,9 @@
     ></div>
 
     {#snippet actions()}
-      {#if copyable && !hasHeader}
+      {#if headerActions}
+        {@render headerActions()}
+      {:else if copyable && !hasHeader}
         <CopyButton
           {copyIconTitle}
           {copySuccessIconTitle}
diff --git a/src/lib/i18n/locales/en/common.ts b/src/lib/i18n/locales/en/common.ts
index 6a8dc29988..6e32db8744 100644
--- a/src/lib/i18n/locales/en/common.ts
+++ b/src/lib/i18n/locales/en/common.ts
@@ -169,6 +169,7 @@ export const Strings = {
   'not-equal-to': 'Not equal to',
   'encode-failed': 'Data encoding failed',
   'decode-failed': 'Data decoding failed',
+  'download-failed': 'Download failed',
   'job-id': 'Job ID',
   'auto-refresh': 'Auto refresh',
   'auto-refresh-tooltip': '{{ interval }} second page refresh',
diff --git a/src/lib/services/data-encoder.ts b/src/lib/services/data-encoder.ts
index 279dbf2ebb..0c3989bc50 100644
--- a/src/lib/services/data-encoder.ts
+++ b/src/lib/services/data-encoder.ts
@@ -5,7 +5,7 @@ import {
   setLastDataEncoderFailure,
   setLastDataEncoderSuccess,
 } from '$lib/stores/data-encoder-config';
-import type { Payloads } from '$lib/types';
+import type { Payload, Payloads } from '$lib/types';
 import type { NetworkError } from '$lib/types/global';
 import { getAccessToken, getIdToken } from '$lib/utilities/core-provider';
 import {
@@ -18,11 +18,15 @@ import { stringifyWithBigInt } from '$lib/utilities/parse-with-big-int';
 
 export type PotentialPayloads = { payloads: unknown[] };
 
+export const NO_CODEC_SERVER_CONFIGURED_ERROR = new Error(
+  'No codec server configured',
+);
+
 export async function codeServerRequest({
   type,
   payloads,
 }: {
-  type: 'decode' | 'encode';
+  type: 'decode' | 'encode' | 'download';
   payloads: PotentialPayloads;
 }): Promise<Payloads> {
   const settings = page.data.settings;
@@ -31,7 +35,7 @@ export async function codeServerRequest({
 
   if (!endpoint) {
     if (type === 'decode') return payloads;
-    throw new Error('No codec endpoint configured');
+    throw NO_CODEC_SERVER_CONFIGURED_ERROR;
   }
 
   const passAccessToken = getCodecPassAccessToken(settings);
@@ -71,10 +75,10 @@ export async function codeServerRequest({
         body: stringifyWithBigInt(payloads),
       };
 
-  const decoderResponse: Promise<PotentialPayloads> = fetch(
-    endpoint + `/${type}`,
-    requestOptions,
-  )
+  const url = new URL(type, endpoint);
+  url.searchParams.set('preserveStorageRefs', 'true');
+
+  const decoderResponse: Promise<PotentialPayloads> = fetch(url, requestOptions)
     .then((response) => {
       if (response.ok === false) {
         throw {
@@ -93,7 +97,9 @@ export async function codeServerRequest({
       return response;
     })
     .catch((err: unknown) => {
-      setLastDataEncoderFailure(err);
+      if (type !== 'download') {
+        setLastDataEncoderFailure(err);
+      }
       if (type === 'decode') {
         return payloads;
       } else {
@@ -119,3 +125,12 @@ export async function encodePayloadsWithCodec({
 }): Promise<Payloads> {
   return codeServerRequest({ type: 'encode', payloads });
 }
+
+export async function downloadExternalPayloadWithCodec(
+  payload: Payload,
+): Promise<Payloads> {
+  return codeServerRequest({
+    type: 'download',
+    payloads: { payloads: [payload] },
+  });
+}
diff --git a/src/lib/utilities/decode-payload.ts b/src/lib/utilities/decode-payload.ts
index d78ab3a7bd..3e9b25b0ac 100644
--- a/src/lib/utilities/decode-payload.ts
+++ b/src/lib/utilities/decode-payload.ts
@@ -33,6 +33,10 @@ export type ParsedPayload = {
   metadata: ParsedMetadata;
 };
 
+export type ParsedExternalPayload = ParsedPayload & {
+  externalPayloads: { sizeBytes: number }[];
+};
+
 /**
  * Decoding TL;DR
  * Decoding includes either 1 or 2 phases - "parse" and "decode"
@@ -113,6 +117,7 @@ export function parseRawPayloadToJSON(
     return {
       metadata,
       data,
+      externalPayloads: payload.externalPayloads ?? [],
     };
   } catch (_e) {
     console.warn('Could not parse payload: ', _e);
@@ -237,8 +242,23 @@ const keyIs = (key: string, ...validKeys: string[]) => {
 export const isRawPayload = (payload: unknown): payload is Payload => {
   if (!isObject(payload)) return false;
   const keys = Object.keys(payload);
+  return keys.length >= 2 && keys.includes('metadata') && keys.includes('data');
+};
+
+export const isParsedPayload = (payload: unknown): payload is ParsedPayload => {
+  if (!isObject(payload)) return false;
+  const keys = Object.keys(payload);
+  return keys.length >= 2 && keys.includes('metadata') && keys.includes('data');
+};
+
+export const isExternallyStoredRawPayload = (
+  payload: unknown,
+): payload is ParsedExternalPayload => {
   return (
-    keys.length === 2 && keys.includes('metadata') && keys.includes('data')
+    isParsedPayload(payload) &&
+    has(payload.metadata, 'messageType') &&
+    payload.metadata.messageType ===
+      'temporal.api.sdk.v1.ExternalStorageReference'
   );
 };
 
@@ -275,17 +295,27 @@ export async function decodePayloadAndParseDataToJSON(
   return parseRawPayloadToJSON(decoded[0], returnDataOnly);
 }
 
-export const decodePayloadsAndParseDataToJSON = async (
+export async function decodePayloadsAndParseDataToJSON(
+  payload: Payloads,
+): Promise<unknown[]>;
+export async function decodePayloadsAndParseDataToJSON(
+  payload: Payloads,
+  returnDataOnly: false,
+): Promise<ParsedPayload[]>;
+export async function decodePayloadsAndParseDataToJSON(
   payloads: Payloads | null | undefined,
-): Promise<unknown[]> => {
+  returnDataOnly: boolean = true,
+): Promise<unknown[]> {
   const decoded = await decodePayloadsWithRemoteCodec(payloads.payloads);
 
   if (!decoded || !decoded[0]) {
     return [null];
   }
 
-  return decoded.map((payload) => parseRawPayloadToJSON(payload));
-};
+  return decoded.map((payload) =>
+    parseRawPayloadToJSON(payload, returnDataOnly),
+  );
+}
 
 /**
  * Phase 2 internal implementation shared by {@link decodeEventAttributes} and