diff --git a/frontend/src/components/canvas/edges/__tests__/HomelableEdge.label.test.tsx b/frontend/src/components/canvas/edges/__tests__/HomelableEdge.label.test.tsx
new file mode 100644
index 0000000..1468e4e
--- /dev/null
+++ b/frontend/src/components/canvas/edges/__tests__/HomelableEdge.label.test.tsx
@@ -0,0 +1,70 @@
+import { describe, it, expect, vi } from 'vitest'
+import { render } from '@testing-library/react'
+import { ReactFlowProvider } from '@xyflow/react'
+import type { EdgeProps, Edge } from '@xyflow/react'
+import type { EdgeData } from '@/types'
+
+/**
+ * Issue #183 — connection labels must support multiple lines.
+ *
+ * The label is a free-text string; newlines entered in the EdgeModal textarea
+ * are stored verbatim. The rendered label div must preserve those newlines
+ * (`whitespace-pre-line`) instead of collapsing them into a single line.
+ *
+ * <EdgeLabelRenderer> normally portals into a node that only exists inside a
+ * full <ReactFlow> host, so we stub it to a passthrough to render the label
+ * markup directly.
+ */
+vi.mock('@xyflow/react', async (importOriginal) => {
+  const actual = await importOriginal<typeof import('@xyflow/react')>()
+  return {
+    ...actual,
+    EdgeLabelRenderer: ({ children }: { children: React.ReactNode }) => <>{children}</>,
+  }
+})
+
+const { HomelableEdge } = await import('../index')
+
+function renderEdge(data: Partial<EdgeData> = {}) {
+  const props = {
+    id: 'e1',
+    source: 'a',
+    target: 'b',
+    sourceX: 0,
+    sourceY: 0,
+    targetX: 100,
+    targetY: 100,
+    sourcePosition: 'bottom',
+    targetPosition: 'top',
+    data: { type: 'ethernet', ...data } as EdgeData,
+    selected: false,
+  } as unknown as EdgeProps<Edge<EdgeData>>
+
+  return render(
+    <ReactFlowProvider>
+      <svg>
+        <HomelableEdge {...props} />
+      </svg>
+    </ReactFlowProvider>,
+  )
+}
+
+describe('HomelableEdge label', () => {
+  it('renders the label text', () => {
+    const { getByText } = renderEdge({ label: 'uplink' })
+    expect(getByText('uplink')).toBeTruthy()
+  })
+
+  it('preserves newlines in the rendered label (issue #183)', () => {
+    const { container } = renderEdge({ label: 'line one\nline two' })
+    const label = Array.from(container.querySelectorAll('div.whitespace-pre-line')).find((d) =>
+      d.textContent === 'line one\nline two',
+    )
+    expect(label).toBeTruthy()
+  })
+
+  it('renders no label div when label is empty', () => {
+    const { container } = renderEdge({ label: undefined })
+    expect(container.querySelector('div.whitespace-pre-line')).toBeNull()
+  })
+})
diff --git a/frontend/src/components/canvas/edges/index.tsx b/frontend/src/components/canvas/edges/index.tsx
index b7e6afd..bae77b8 100644
--- a/frontend/src/components/canvas/edges/index.tsx
+++ b/frontend/src/components/canvas/edges/index.tsx
@@ -406,7 +406,7 @@ export function HomelableEdge({ id, source, target, sourceHandleId, targetHandle
       <EdgeLabelRenderer>
         {data?.label && (
           <div
-            className="absolute pointer-events-none font-mono text-[10px] px-1.5 py-0.5 rounded"
+            className="absolute pointer-events-none font-mono text-[10px] px-1.5 py-0.5 rounded whitespace-pre-line text-center"
             style={{
               transform: `translate(-50%, -50%) translate(${labelPosition.x}px, ${labelPosition.y}px)`,
               background: theme.colors.edgeLabelBackground,
diff --git a/frontend/src/components/modals/EdgeModal.tsx b/frontend/src/components/modals/EdgeModal.tsx
index 720572d..ccb04ab 100644
--- a/frontend/src/components/modals/EdgeModal.tsx
+++ b/frontend/src/components/modals/EdgeModal.tsx
@@ -4,6 +4,7 @@ import { RotateCcw } from 'lucide-react'
 import { Dialog, DialogContent, DialogHeader, DialogTitle } from '@/components/ui/dialog'
 import { Button } from '@/components/ui/button'
 import { Input } from '@/components/ui/input'
+import { Textarea } from '@/components/ui/textarea'
 import { Label } from '@/components/ui/label'
 import { Select, SelectContent, SelectItem, SelectTrigger, SelectValue } from '@/components/ui/select'
 import { EDGE_TYPE_LABELS, type EdgeData, type EdgePathStyle, type EdgeType } from '@/types'
@@ -44,7 +45,7 @@ export function EdgeModal({ open, onClose, onSubmit, onDelete, onClearWaypoints,
     e.preventDefault()
     onSubmit({
       type,
-      label: label || undefined,
+      label: label.trim() || undefined,
       vlan_id: type === 'vlan' && vlanId ? parseInt(vlanId) : undefined,
       custom_color: customColor,
       path_style: pathStyle,
@@ -96,12 +97,13 @@ export function EdgeModal({ open, onClose, onSubmit, onDelete, onClearWaypoints,
           )}
 
           <div className="flex flex-col gap-1.5">
-            <Label className="text-xs text-muted-foreground">Label <span className="text-muted-foreground/50">(optional)</span></Label>
-            <Input
+            <Label className="text-xs text-muted-foreground">Label <span className="text-muted-foreground/50">(optional, multi-line)</span></Label>
+            <Textarea
               value={label}
               onChange={(e) => setLabel(e.target.value)}
-              placeholder="e.g. 1G, trunk..."
-              className={`bg-[#21262d] border-[#30363d] text-sm h-8 ${modalStyles['modal-radius']}`}
+              placeholder={'e.g. 1G, trunk...\nsecond line'}
+              rows={2}
+              className={`bg-[#21262d] border-[#30363d] text-sm min-h-16 resize-none ${modalStyles['modal-radius']}`}
             />
           </div>
 
diff --git a/frontend/src/components/modals/__tests__/EdgeModal.test.tsx b/frontend/src/components/modals/__tests__/EdgeModal.test.tsx
index c24a0bf..51e6faa 100644
--- a/frontend/src/components/modals/__tests__/EdgeModal.test.tsx
+++ b/frontend/src/components/modals/__tests__/EdgeModal.test.tsx
@@ -47,11 +47,32 @@ describe('EdgeModal', () => {
   it('calls onSubmit with label when filled', () => {
     const onSubmit = vi.fn()
     render(<EdgeModal open onClose={vi.fn()} onSubmit={onSubmit} />)
-    fireEvent.change(screen.getByPlaceholderText('e.g. 1G, trunk...'), { target: { value: 'uplink' } })
+    fireEvent.change(screen.getByPlaceholderText(/e\.g\. 1G, trunk/), { target: { value: 'uplink' } })
     fireEvent.click(screen.getByRole('button', { name: 'Connect' }))
     expect(onSubmit.mock.calls[0][0].label).toBe('uplink')
   })
 
+  it('preserves newlines in label so it can span multiple lines (issue #183)', () => {
+    const onSubmit = vi.fn()
+    render(<EdgeModal open onClose={vi.fn()} onSubmit={onSubmit} />)
+    fireEvent.change(screen.getByPlaceholderText(/e\.g\. 1G, trunk/), { target: { value: 'line one\nline two' } })
+    fireEvent.click(screen.getByRole('button', { name: 'Connect' }))
+    expect(onSubmit.mock.calls[0][0].label).toBe('line one\nline two')
+  })
+
+  it('trims surrounding whitespace/blank lines from label on submit', () => {
+    const onSubmit = vi.fn()
+    render(<EdgeModal open onClose={vi.fn()} onSubmit={onSubmit} />)
+    fireEvent.change(screen.getByPlaceholderText(/e\.g\. 1G, trunk/), { target: { value: '  a\nb\n\n' } })
+    fireEvent.click(screen.getByRole('button', { name: 'Connect' }))
+    expect(onSubmit.mock.calls[0][0].label).toBe('a\nb')
+  })
+
+  it('renders the label field as a textarea (multi-line input)', () => {
+    render(<EdgeModal open onClose={vi.fn()} onSubmit={vi.fn()} />)
+    expect(screen.getByPlaceholderText(/e\.g\. 1G, trunk/).tagName).toBe('TEXTAREA')
+  })
+
   it('omits label from payload when empty', () => {
     const onSubmit = vi.fn()
     render(<EdgeModal open onClose={vi.fn()} onSubmit={onSubmit} />)
@@ -171,7 +192,7 @@ describe('EdgeModal', () => {
 
   it('pre-fills label from initial prop', () => {
     render(<EdgeModal open onClose={vi.fn()} onSubmit={vi.fn()} initial={{ label: 'trunk' }} />)
-    const input = screen.getByPlaceholderText('e.g. 1G, trunk...') as HTMLInputElement
+    const input = screen.getByPlaceholderText(/e\.g\. 1G, trunk/) as HTMLTextAreaElement
     expect(input.value).toBe('trunk')
   })
 
diff --git a/frontend/src/components/ui/textarea.tsx b/frontend/src/components/ui/textarea.tsx
new file mode 100644
index 0000000..bb823b4
--- /dev/null
+++ b/frontend/src/components/ui/textarea.tsx
@@ -0,0 +1,18 @@
+import * as React from "react"
+
+import { cn } from "@/lib/utils"
+
+function Textarea({ className, ...props }: React.ComponentProps<"textarea">) {
+  return (
+    <textarea
+      data-slot="textarea"
+      className={cn(
+        "min-h-16 w-full min-w-0 rounded-lg border border-input bg-transparent px-2.5 py-1.5 text-base transition-colors outline-none placeholder:text-muted-foreground focus-visible:border-ring focus-visible:ring-3 focus-visible:ring-ring/50 disabled:pointer-events-none disabled:cursor-not-allowed disabled:bg-input/50 disabled:opacity-50 aria-invalid:border-destructive aria-invalid:ring-3 aria-invalid:ring-destructive/20 md:text-sm dark:bg-input/30 dark:disabled:bg-input/80 dark:aria-invalid:border-destructive/50 dark:aria-invalid:ring-destructive/40",
+        className
+      )}
+      {...props}
+    />
+  )
+}
+
+export { Textarea }