diff --git a/packages/ra-ui-materialui/src/input/CheckboxGroupInput.tsx b/packages/ra-ui-materialui/src/input/CheckboxGroupInput.tsx
index cf4001203f1..c3021b94772 100644
--- a/packages/ra-ui-materialui/src/input/CheckboxGroupInput.tsx
+++ b/packages/ra-ui-materialui/src/input/CheckboxGroupInput.tsx
@@ -16,6 +16,7 @@ import InputHelperText from './InputHelperText';
 import classnames from 'classnames';
 import Labeled from './Labeled';
 import { LinearProgress } from '../layout';
+import { ClassesOverride } from '../types';
 
 /**
  * An Input component for a checkbox group, using an array of objects for the options
@@ -79,9 +80,7 @@ import { LinearProgress } from '../layout';
  *
  * The object passed as `options` props is passed to the material-ui <Checkbox> components
  */
-const CheckboxGroupInput: FunctionComponent<
-    ChoicesInputProps<CheckboxProps> & FormControlProps
-> = props => {
+const CheckboxGroupInput: FunctionComponent<CheckboxGroupInputProps> = props => {
     const {
         choices = [],
         className,
@@ -260,4 +259,10 @@ CheckboxGroupInput.defaultProps = {
     row: true,
 };
 
+export interface CheckboxGroupInputProps
+    extends ChoicesInputProps<CheckboxProps>,
+        FormControlProps {
+    classes?: ClassesOverride<typeof useStyles>;
+}
+
 export default CheckboxGroupInput;
diff --git a/packages/ra-ui-materialui/src/input/index.ts b/packages/ra-ui-materialui/src/input/index.ts
index 7e168318a11..fba4e7f05b5 100644
--- a/packages/ra-ui-materialui/src/input/index.ts
+++ b/packages/ra-ui-materialui/src/input/index.ts
@@ -4,7 +4,9 @@ import AutocompleteArrayInput, {
 } from './AutocompleteArrayInput';
 import AutocompleteInput, { AutocompleteInputProps } from './AutocompleteInput';
 import BooleanInput from './BooleanInput';
-import CheckboxGroupInput from './CheckboxGroupInput';
+import CheckboxGroupInput, {
+    CheckboxGroupInputProps,
+} from './CheckboxGroupInput';
 import DateInput from './DateInput';
 import DateTimeInput from './DateTimeInput';
 import FileInput from './FileInput';
@@ -56,4 +58,8 @@ export {
     sanitizeInputRestProps,
 };
 
-export type { AutocompleteInputProps, AutocompleteArrayInputProps };
+export type {
+    AutocompleteInputProps,
+    AutocompleteArrayInputProps,
+    CheckboxGroupInputProps,
+};