diff --git a/packages/babel-plugin-transform-typescript/src/index.js b/packages/babel-plugin-transform-typescript/src/index.js
index b302ea5aa751..4073d96c5948 100644
--- a/packages/babel-plugin-transform-typescript/src/index.js
+++ b/packages/babel-plugin-transform-typescript/src/index.js
@@ -51,9 +51,9 @@ export default declare((api, opts) => {
   const JSX_PRAGMA_REGEX = /\*?\s*@jsx((?:Frag)?)\s+([^\s]+)/;
 
   const {
+    allowNamespaces = true,
     jsxPragma = "React.createElement",
     jsxPragmaFrag = "React.Fragment",
-    allowNamespaces = false,
     onlyRemoveTypeImports = false,
   } = opts;
 
diff --git a/packages/babel-preset-typescript/src/normalize-options.js b/packages/babel-preset-typescript/src/normalize-options.js
index dcf7d4261254..71d0f2b722e7 100644
--- a/packages/babel-preset-typescript/src/normalize-options.js
+++ b/packages/babel-preset-typescript/src/normalize-options.js
@@ -2,7 +2,7 @@ import { OptionValidator } from "@babel/helper-validator-option";
 const v = new OptionValidator("@babel/preset-typescript");
 
 export default function normalizeOptions(options = {}) {
-  let { allowNamespaces, jsxPragma, onlyRemoveTypeImports } = options;
+  let { allowNamespaces = true, jsxPragma, onlyRemoveTypeImports } = options;
 
   if (process.env.BABEL_8_BREAKING) {
     const TopLevelOptions = {
diff --git a/packages/babel-preset-typescript/test/normalize-options.spec.js b/packages/babel-preset-typescript/test/normalize-options.spec.js
index b84c91c4f41a..0b99d8e4b9f1 100644
--- a/packages/babel-preset-typescript/test/normalize-options.spec.js
+++ b/packages/babel-preset-typescript/test/normalize-options.spec.js
@@ -78,7 +78,7 @@ describe("normalize options", () => {
       expect(normalizeOptions({})).toMatchInlineSnapshot(`
         Object {
           "allExtensions": false,
-          "allowNamespaces": undefined,
+          "allowNamespaces": true,
           "isTSX": false,
           "jsxPragma": undefined,
           "jsxPragmaFrag": "React.Fragment",