diff --git a/get-shit-done/bin/lib/phase.cjs b/get-shit-done/bin/lib/phase.cjs
index 3bda6758b..4df2beb60 100644
--- a/get-shit-done/bin/lib/phase.cjs
+++ b/get-shit-done/bin/lib/phase.cjs
@@ -712,7 +712,7 @@ function cmdPhaseComplete(cwd, phaseNum, raw) {
         `(-\\s*\\[)[ ](\\]\\s*.*Phase\\s+${escapeRegex(phaseNum)}[:\\s][^\\n]*)`,
         'i'
       );
-      roadmapContent = replaceInCurrentMilestone(roadmapContent, checkboxPattern, `$1x$2 (completed ${today})`);
+      roadmapContent = roadmapContent.replace(checkboxPattern, `$1x$2 (completed ${today})`);
 
       // Progress table: update Status to Complete, add date (handles 4 or 5 column tables)
       const phaseEscaped = escapeRegex(phaseNum);
diff --git a/tests/bug-1998-phase-complete-checkbox.test.cjs b/tests/bug-1998-phase-complete-checkbox.test.cjs
new file mode 100644
index 000000000..61aeafb31
--- /dev/null
+++ b/tests/bug-1998-phase-complete-checkbox.test.cjs
@@ -0,0 +1,137 @@
+/**
+ * Regression tests for bug #1998
+ *
+ * phase complete must update the top-level overview bullet checkbox
+ * (- [ ] Phase N: → - [x] Phase N:) in addition to the Progress table row.
+ *
+ * Root cause: the checkbox update used replaceInCurrentMilestone() which
+ * scopes to content after </details>, missing the current milestone's
+ * overview bullets that appear before any <details> blocks.
+ */
+
+'use strict';
+
+const { describe, test, beforeEach, afterEach } = require('node:test');
+const assert = require('node:assert/strict');
+const fs = require('node:fs');
+const path = require('node:path');
+const os = require('node:os');
+const { execFileSync } = require('node:child_process');
+
+const gsdTools = path.resolve(__dirname, '..', 'get-shit-done', 'bin', 'gsd-tools.cjs');
+
+describe('bug #1998: phase complete updates overview checkbox', () => {
+  let tmpDir;
+  let planningDir;
+
+  beforeEach(() => {
+    tmpDir = fs.mkdtempSync(path.join(os.tmpdir(), 'gsd-1998-'));
+    planningDir = path.join(tmpDir, '.planning');
+    fs.mkdirSync(planningDir, { recursive: true });
+
+    // Minimal config
+    fs.writeFileSync(
+      path.join(planningDir, 'config.json'),
+      JSON.stringify({ project_code: 'TEST' })
+    );
+
+    // Minimal STATE.md
+    fs.writeFileSync(
+      path.join(planningDir, 'STATE.md'),
+      '---\ncurrent_phase: 1\nstatus: executing\n---\n# State\n'
+    );
+  });
+
+  afterEach(() => {
+    fs.rmSync(tmpDir, { recursive: true, force: true });
+  });
+
+  test('checkbox updated when no archived milestones exist', () => {
+    const phasesDir = path.join(planningDir, 'phases', '01-foundation');
+    fs.mkdirSync(phasesDir, { recursive: true });
+    fs.writeFileSync(
+      path.join(phasesDir, '01-1-SUMMARY.md'),
+      '---\nstatus: complete\n---\n# Summary\nDone.'
+    );
+    fs.writeFileSync(
+      path.join(phasesDir, '01-1-PLAN.md'),
+      '---\nphase: 1\nplan: 1\n---\n# Plan 1\n'
+    );
+
+    const roadmapPath = path.join(planningDir, 'ROADMAP.md');
+    fs.writeFileSync(roadmapPath, [
+      '# Roadmap',
+      '',
+      '## Phases',
+      '',
+      '- [ ] **Phase 1: Foundation** - core setup',
+      '- [ ] **Phase 2: Features** - add features',
+      '',
+      '## Progress',
+      '',
+      '| Phase | Plans | Status | Completed |',
+      '|-------|-------|--------|-----------|',
+      '| 1. Foundation | 0/1 | Pending | - |',
+      '| 2. Features | 0/1 | Pending | - |',
+    ].join('\n'));
+
+    try {
+      execFileSync('node', [gsdTools, 'phase', 'complete', '1'], { cwd: tmpDir, timeout: 10000 });
+    } catch {
+      // Command may exit non-zero if STATE.md update fails, but ROADMAP.md update happens first
+    }
+
+    const result = fs.readFileSync(roadmapPath, 'utf-8');
+    assert.match(result, /- \[x\] \*\*Phase 1: Foundation\*\*/, 'overview checkbox should be checked');
+    assert.match(result, /- \[ \] \*\*Phase 2: Features\*\*/, 'phase 2 checkbox should remain unchecked');
+  });
+
+  test('checkbox updated when archived milestones exist in <details>', () => {
+    const phasesDir = path.join(planningDir, 'phases', '01-setup');
+    fs.mkdirSync(phasesDir, { recursive: true });
+    fs.writeFileSync(
+      path.join(phasesDir, '01-1-SUMMARY.md'),
+      '---\nstatus: complete\n---\n# Summary\nDone.'
+    );
+    fs.writeFileSync(
+      path.join(phasesDir, '01-1-PLAN.md'),
+      '---\nphase: 1\nplan: 1\n---\n# Plan 1\n'
+    );
+
+    const roadmapPath = path.join(planningDir, 'ROADMAP.md');
+    fs.writeFileSync(roadmapPath, [
+      '# Roadmap v2.0',
+      '',
+      '## Phases',
+      '',
+      '- [ ] **Phase 1: Setup** - initial setup',
+      '- [ ] **Phase 2: Build** - build features',
+      '',
+      '## Progress',
+      '',
+      '| Phase | Plans | Status | Completed |',
+      '|-------|-------|--------|-----------|',
+      '| 1. Setup | 0/1 | Pending | - |',
+      '| 2. Build | 0/1 | Pending | - |',
+      '',
+      '<details>',
+      '<summary>v1.0 (Archived)</summary>',
+      '',
+      '## v1.0 Phases',
+      '- [x] **Phase 1: Init** - initialization',
+      '- [x] **Phase 2: Deploy** - deployment',
+      '',
+      '</details>',
+    ].join('\n'));
+
+    try {
+      execFileSync('node', [gsdTools, 'phase', 'complete', '1'], { cwd: tmpDir, timeout: 10000 });
+    } catch {
+      // May exit non-zero
+    }
+
+    const result = fs.readFileSync(roadmapPath, 'utf-8');
+    assert.match(result, /- \[x\] \*\*Phase 1: Setup\*\*/, 'current milestone checkbox should be checked');
+    assert.match(result, /- \[ \] \*\*Phase 2: Build\*\*/, 'phase 2 checkbox should remain unchecked');
+  });
+});