diff --git a/.changeset/fix-react-18-context-providers.md b/.changeset/fix-react-18-context-providers.md
new file mode 100644
index 0000000000..87b18b1cd6
--- /dev/null
+++ b/.changeset/fix-react-18-context-providers.md
@@ -0,0 +1,5 @@
+---
+"@cloudflare/kumo": patch
+---
+
+Fix Combobox and Autocomplete rendering in React 18 by using the explicit context provider API.
diff --git a/packages/kumo/src/components/autocomplete/autocomplete.tsx b/packages/kumo/src/components/autocomplete/autocomplete.tsx
index 5b5aaf3468..0165eeea8f 100644
--- a/packages/kumo/src/components/autocomplete/autocomplete.tsx
+++ b/packages/kumo/src/components/autocomplete/autocomplete.tsx
@@ -116,9 +116,9 @@ function Root<ItemValue>({
     items?: readonly ItemValue[];
   };
   const control = (
-    <AutocompleteContext value={{ hasError: Boolean(error) }}>
+    <AutocompleteContext.Provider value={{ hasError: Boolean(error) }}>
       <AutocompleteBase.Root {...rootProps}>{children}</AutocompleteBase.Root>
-    </AutocompleteContext>
+    </AutocompleteContext.Provider>
   );
 
   if (label) {
diff --git a/packages/kumo/src/components/combobox/combobox.tsx b/packages/kumo/src/components/combobox/combobox.tsx
index 934092bb87..04b4a57004 100644
--- a/packages/kumo/src/components/combobox/combobox.tsx
+++ b/packages/kumo/src/components/combobox/combobox.tsx
@@ -167,9 +167,9 @@ function Root<Value, Multiple extends boolean | undefined = false>({
   size?: KumoComboboxSize;
 }) {
   const comboboxControl = (
-    <ComboboxContext value={{ size, hasError: Boolean(error) }}>
+    <ComboboxContext.Provider value={{ size, hasError: Boolean(error) }}>
       <ComboboxBase.Root {...props}>{children}</ComboboxBase.Root>
-    </ComboboxContext>
+    </ComboboxContext.Provider>
   );
 
   // Render with Field wrapper if label, description, or error are provided