diff --git a/.changeset/happy-taxis-compare.md b/.changeset/happy-taxis-compare.md
new file mode 100644
index 00000000000..f7c15c5e33a
--- /dev/null
+++ b/.changeset/happy-taxis-compare.md
@@ -0,0 +1,5 @@
+---
+"@primer/components": patch
+---
+
+Migrate `Flex` to TypeScript
diff --git a/src/Flex.js b/src/Flex.tsx
similarity index 70%
rename from src/Flex.js
rename to src/Flex.tsx
index 5f0a95f7c09..ce69f2e303b 100644
--- a/src/Flex.js
+++ b/src/Flex.tsx
@@ -1,6 +1,7 @@
 import styled from 'styled-components'
-import theme from './theme'
 import Box from './Box'
+import theme from './theme'
+import {ComponentProps} from './utils/types'
 
 const Flex = styled(Box)``
 
@@ -13,4 +14,5 @@ Flex.propTypes = {
   ...Box.propTypes
 }
 
+export type FlexProps = ComponentProps<typeof Flex>
 export default Flex
diff --git a/src/__tests__/Flex.js b/src/__tests__/Flex.tsx
similarity index 100%
rename from src/__tests__/Flex.js
rename to src/__tests__/Flex.tsx
diff --git a/src/__tests__/__snapshots__/Flex.js.snap b/src/__tests__/__snapshots__/Flex.tsx.snap
similarity index 100%
rename from src/__tests__/__snapshots__/Flex.js.snap
rename to src/__tests__/__snapshots__/Flex.tsx.snap