diff --git a/packages/types/src/index.ts b/packages/types/src/index.ts
index aa3876e5e8ea..2dabfb31466e 100644
--- a/packages/types/src/index.ts
+++ b/packages/types/src/index.ts
@@ -62,6 +62,7 @@ export type { Severity, SeverityLevel } from './severity';
 export type { Span, SpanContext } from './span';
 export type { StackFrame } from './stackframe';
 export type { Stacktrace, StackParser, StackLineParser, StackLineParserFn } from './stacktrace';
+export type { TextEncoderInternal } from './textencoder';
 export type {
   CustomSamplingContext,
   Measurements,
diff --git a/packages/types/src/textencoder.ts b/packages/types/src/textencoder.ts
new file mode 100644
index 000000000000..9071c14c007c
--- /dev/null
+++ b/packages/types/src/textencoder.ts
@@ -0,0 +1,16 @@
+/**
+ * Vendored type from TS 3.8 `typescript/lib/lib.dom.d.ts`.
+ *
+ * Type is vendored in so that users don't have to opt-in to DOM types.
+ */
+export interface TextEncoderCommon {
+  /**
+   * Returns "utf-8".
+   */
+  readonly encoding: string;
+}
+
+// Combination of global TextEncoder and Node require('util').TextEncoder
+export interface TextEncoderInternal extends TextEncoderCommon {
+  encode(input?: string): Uint8Array;
+}
diff --git a/packages/types/src/transport.ts b/packages/types/src/transport.ts
index 6d358dc7ddc9..dae3ddd5f920 100644
--- a/packages/types/src/transport.ts
+++ b/packages/types/src/transport.ts
@@ -1,6 +1,7 @@
 import { EventDropReason } from './clientreport';
 import { DataCategory } from './datacategory';
 import { Envelope } from './envelope';
+import { TextEncoderInternal } from './textencoder';
 
 export type TransportRequest = {
   body: string | Uint8Array;
@@ -15,11 +16,6 @@ export type TransportMakeRequestResponse = {
   };
 };
 
-// Combination of global TextEncoder and Node require('util').TextEncoder
-interface TextEncoderInternal extends TextEncoderCommon {
-  encode(input?: string): Uint8Array;
-}
-
 export interface InternalBaseTransportOptions {
   bufferSize?: number;
   recordDroppedEvent: (reason: EventDropReason, dataCategory: DataCategory) => void;
diff --git a/packages/utils/src/envelope.ts b/packages/utils/src/envelope.ts
index 1bc69915345d..f203cef51284 100644
--- a/packages/utils/src/envelope.ts
+++ b/packages/utils/src/envelope.ts
@@ -1,4 +1,12 @@
-import { Attachment, AttachmentItem, DataCategory, Envelope, EnvelopeItem, EnvelopeItemType } from '@sentry/types';
+import {
+  Attachment,
+  AttachmentItem,
+  DataCategory,
+  Envelope,
+  EnvelopeItem,
+  EnvelopeItemType,
+  TextEncoderInternal,
+} from '@sentry/types';
 
 import { dropUndefinedKeys } from './object';
 
@@ -36,11 +44,6 @@ export function forEachEnvelopeItem<E extends Envelope>(
   });
 }
 
-// Combination of global TextEncoder and Node require('util').TextEncoder
-interface TextEncoderInternal extends TextEncoderCommon {
-  encode(input?: string): Uint8Array;
-}
-
 function encodeUTF8(input: string, textEncoder?: TextEncoderInternal): Uint8Array {
   const utf8 = textEncoder || new TextEncoder();
   return utf8.encode(input);