diff --git a/.changeset/modern-lizards-play.md b/.changeset/modern-lizards-play.md
new file mode 100644
index 00000000000..fd865cd0210
--- /dev/null
+++ b/.changeset/modern-lizards-play.md
@@ -0,0 +1,5 @@
+---
+"@primer/components": patch
+---
+
+Migrate theme to TypeScript
diff --git a/src/__tests__/themeGet.js b/src/__tests__/themeGet.ts
similarity index 100%
rename from src/__tests__/themeGet.js
rename to src/__tests__/themeGet.ts
diff --git a/src/theme-preval.js b/src/theme-preval.ts
similarity index 97%
rename from src/theme-preval.js
rename to src/theme-preval.ts
index 9845f5b76bf..654e2057c4e 100644
--- a/src/theme-preval.js
+++ b/src/theme-preval.ts
@@ -1,12 +1,10 @@
-// @preval
-
-const {colors: colorPrimitives, typography} = require('@primer/primitives')
-const {lighten, rgba, desaturate} = require('polished')
+import {colors as colorPrimitives, typography} from '@primer/primitives'
+import {lighten, rgba, desaturate} from 'polished'
 
 const {lineHeights} = typography
 const {black, white, pink, gray, blue, green, orange, purple, red, yellow} = colorPrimitives
 // General
-const colors = {
+export const colors = {
   bodytext: gray[9],
   black,
   white,
@@ -350,7 +348,7 @@ const stateLabels = {
   }
 }
 
-const theme = {
+export const theme = {
   // General
   borderWidths,
   breakpoints,
@@ -373,11 +371,6 @@ const theme = {
   stateLabels
 }
 
-module.exports = {
-  theme,
-  colors
-}
-
-function fontStack(fonts) {
+function fontStack(fonts: string[]) {
   return fonts.map(font => (font.includes(' ') ? `"${font}"` : font)).join(', ')
 }
diff --git a/src/theme.js b/src/theme.js
deleted file mode 100644
index 3a0afbdd1af..00000000000
--- a/src/theme.js
+++ /dev/null
@@ -1,5 +0,0 @@
-const themeExport = require('./theme-preval')
-const {theme, colors} = themeExport
-
-export default theme
-export {colors}
diff --git a/src/theme.ts b/src/theme.ts
new file mode 100644
index 00000000000..494c8060eb4
--- /dev/null
+++ b/src/theme.ts
@@ -0,0 +1,4 @@
+import {theme, colors} from /* preval */ './theme-preval'
+
+export default theme
+export {colors}