diff --git a/.changeset/select-panel-display-in-viewport.md b/.changeset/select-panel-display-in-viewport.md
new file mode 100644
index 00000000000..05357d80c04
--- /dev/null
+++ b/.changeset/select-panel-display-in-viewport.md
@@ -0,0 +1,5 @@
+---
+'@primer/react': minor
+---
+
+SelectPanel: Add `displayInViewport` prop
diff --git a/packages/react/src/SelectPanel/SelectPanel.docs.json b/packages/react/src/SelectPanel/SelectPanel.docs.json
index f55961d2614..d7f91b944e1 100644
--- a/packages/react/src/SelectPanel/SelectPanel.docs.json
+++ b/packages/react/src/SelectPanel/SelectPanel.docs.json
@@ -237,6 +237,12 @@
       "type": "boolean",
       "defaultValue": "false",
       "description": "If true, enables client-side list virtualization. Only the visible items plus a small overscan buffer are rendered in the DOM, dramatically improving performance for large lists. Recommended for lists with more than 100 items. Has no effect when `groupMetadata` is provided."
+    },
+    {
+      "name": "displayInViewport",
+      "type": "boolean",
+      "defaultValue": "false",
+      "description": "If true, the panel will attempt to fit entirely into the visible viewport, without having to scroll."
     }
   ],
   "subcomponents": []
diff --git a/packages/react/src/SelectPanel/SelectPanel.test.tsx b/packages/react/src/SelectPanel/SelectPanel.test.tsx
index fae621080c7..de52939b1ac 100644
--- a/packages/react/src/SelectPanel/SelectPanel.test.tsx
+++ b/packages/react/src/SelectPanel/SelectPanel.test.tsx
@@ -10,6 +10,29 @@ import {IconButton} from '../Button'
 import {ArrowLeftIcon} from '@primer/octicons-react'
 import classes from './SelectPanel.test.module.css'
 import {implementsClassName} from '../utils/testing'
+import {getAnchoredPosition} from '@primer/behaviors'
+import type {AnchorPosition} from '@primer/behaviors'
+
+// Mock getAnchoredPosition to verify displayInViewport is forwarded
+vi.mock('@primer/behaviors', async () => {
+  const actual = await vi.importActual('@primer/behaviors')
+  return {
+    ...actual,
+    getAnchoredPosition: vi.fn(
+      (
+        _floatingElement: Element,
+        _anchorElement: Element | DOMRect,
+        _settings?: Partial<{displayInViewport?: boolean}>,
+      ) =>
+        ({
+          top: 100,
+          left: 100,
+          anchorSide: 'outside-bottom',
+          anchorAlign: 'start',
+        }) as AnchorPosition,
+    ),
+  }
+})
 
 // Instead of importing from live-region/__tests__/test-helpers.ts, we define our own getLiveRegion function
 export function getLiveRegion(): LiveRegionElement {
@@ -1734,3 +1757,49 @@ for (const usingRemoveActiveDescendant of [false, true]) {
     })
   })
 }
+
+describe('SelectPanel displayInViewport prop', () => {
+  const mockGetAnchoredPosition = vi.mocked(getAnchoredPosition)
+
+  beforeEach(() => {
+    mockGetAnchoredPosition.mockClear()
+  })
+
+  it('should forward displayInViewport={true} to getAnchoredPosition', async () => {
+    const user = userEvent.setup()
+    render(<BasicSelectPanel displayInViewport={true} />)
+
+    await user.click(screen.getByRole('button', {name: 'Select items'}))
+
+    await waitFor(() => {
+      expect(screen.getByRole('listbox')).toBeInTheDocument()
+    })
+
+    await waitFor(() => {
+      expect(mockGetAnchoredPosition).toHaveBeenCalled()
+    })
+
+    const calls = mockGetAnchoredPosition.mock.calls
+    const lastCall = calls[calls.length - 1]
+    expect(lastCall[2]?.displayInViewport).toBe(true)
+  })
+
+  it('should not set displayInViewport when prop is not provided', async () => {
+    const user = userEvent.setup()
+    render(<BasicSelectPanel />)
+
+    await user.click(screen.getByRole('button', {name: 'Select items'}))
+
+    await waitFor(() => {
+      expect(screen.getByRole('listbox')).toBeInTheDocument()
+    })
+
+    await waitFor(() => {
+      expect(mockGetAnchoredPosition).toHaveBeenCalled()
+    })
+
+    const calls = mockGetAnchoredPosition.mock.calls
+    const lastCall = calls[calls.length - 1]
+    expect(lastCall[2]?.displayInViewport).not.toBe(true)
+  })
+})
diff --git a/packages/react/src/SelectPanel/SelectPanel.tsx b/packages/react/src/SelectPanel/SelectPanel.tsx
index 82cd0812d1b..04667503618 100644
--- a/packages/react/src/SelectPanel/SelectPanel.tsx
+++ b/packages/react/src/SelectPanel/SelectPanel.tsx
@@ -131,7 +131,7 @@ type SelectPanelVariantProps = {variant?: 'anchored'; onCancel?: () => void} | {
 
 export type SelectPanelProps = SelectPanelBaseProps &
   Omit<FilteredActionListProps, 'selectionVariant' | 'variant' | 'message'> &
-  Pick<AnchoredOverlayProps, 'open' | 'height' | 'width' | 'align'> &
+  Pick<AnchoredOverlayProps, 'open' | 'height' | 'width' | 'align' | 'displayInViewport'> &
   AnchoredOverlayWrapperAnchorProps &
   (SelectPanelSingleSelection | SelectPanelMultiSelection) &
   SelectPanelVariantProps
@@ -203,6 +203,7 @@ function Panel({
   showSelectAll = false,
   focusPrependedElements,
   virtualized,
+  displayInViewport,
   ...listProps
 }: SelectPanelProps): JSX.Element {
   const titleId = useId()
@@ -876,6 +877,7 @@ function Panel({
         className={classes.Overlay}
         displayCloseButton={showXCloseIcon}
         closeButtonProps={closeButtonProps}
+        displayInViewport={displayInViewport}
       >
         <div className={classes.Wrapper} data-variant={variant}>
           <div className={classes.Header} data-variant={currentResponsiveVariant}>