diff --git a/dashboard/src/components/workplan-search.js b/dashboard/src/components/workplan-search.js
new file mode 100644
index 0000000..aa355e0
--- /dev/null
+++ b/dashboard/src/components/workplan-search.js
@@ -0,0 +1,22 @@
+/**
+ * Case-insensitive substring match for Overview "Workplans by Repository".
+ * Matches title, repo, domain, filename, owner, and id.
+ *
+ * @param {object} workplan  Row from overview workplan_rows
+ * @param {string} query     Free-text filter
+ * @returns {boolean}
+ */
+export function workplanMatchesSearch(workplan, query) {
+  const q = String(query ?? "").trim().toLowerCase();
+  if (!q) return true;
+  if (!workplan || typeof workplan !== "object") return false;
+  const haystack = [
+    workplan.title,
+    workplan.repo_label,
+    workplan.domain,
+    workplan.workplan_filename,
+    workplan.owner,
+    workplan.id,
+  ].filter(Boolean).join("\n").toLowerCase();
+  return haystack.includes(q);
+}
diff --git a/dashboard/src/docs/overview.md b/dashboard/src/docs/overview.md
index ce827ac..c25808d 100644
--- a/dashboard/src/docs/overview.md
+++ b/dashboard/src/docs/overview.md
@@ -24,6 +24,13 @@ by repository. Each bar is broken into four task-status segments:
 | orange | wait |
 | light grey | todo |
 
+Above the chart:
+
+- **Mode selector** — lifecycle, health, or recently-changed windows (with
+  matching workplan counts in each option).
+- **Text filter** — case-insensitive substring match on title, repository,
+  domain, workplan filename, and owner. Useful when many rows share a mode.
+
 The left axis shows the `domain / repository` label once per repository group.
 The `done/total` count is printed to the right of each bar. Workplans with no
 tasks yet show a grey "— no tasks yet" label.
diff --git a/dashboard/src/index.md b/dashboard/src/index.md
index 3a8edc4..7deb975 100644
--- a/dashboard/src/index.md
+++ b/dashboard/src/index.md
@@ -151,6 +151,8 @@ display(html`<div class="warning" style="display:${summary.error ? '' : 'none'}"
 ## Workplans by Repository
 
 ```js
+import {workplanMatchesSearch} from "./components/workplan-search.js";
+
 // ── Filter workplans by selected mode ───────────────────────────────────────
 // Lifecycle modes match stored canonical status values.
 // Health modes are derived labels; they are not stored lifecycle states.
@@ -246,6 +248,18 @@ function _setChartMode(value) {
   globalThis.__stateHubOverviewChartMode = mode;
   _chartModeState.value = mode;
 }
+
+// Free-text filter over title / repo / domain / workplan filename (persists in-tab).
+const _savedChartSearch = typeof globalThis.__stateHubOverviewChartSearch === "string"
+  ? globalThis.__stateHubOverviewChartSearch
+  : "";
+const _chartSearchState = Mutable(_savedChartSearch);
+
+function _setChartSearch(value) {
+  const q = String(value ?? "");
+  globalThis.__stateHubOverviewChartSearch = q;
+  _chartSearchState.value = q;
+}
 ```
 
 ```js
@@ -265,14 +279,32 @@ _modeSelect.addEventListener("input", () => {
 _modeSelect.addEventListener("change", () => {
   _setChartMode(_modeSelect.value);
 });
-display(_modeSelect);
+
+const _searchInput = html`<input
+  type="search"
+  class="ws-search-input"
+  placeholder="Filter by title, repo, domain…"
+  aria-label="Filter workplans by text"
+  title="Show only workplans matching this text (title, repository, domain, filename)"
+/>`;
+_searchInput.value = String(_chartSearchState ?? "");
+_searchInput.addEventListener("input", () => {
+  _setChartSearch(_searchInput.value);
+});
+
+display(html`<div class="filter-bar ws-mode-bar" data-widget-name="Workplans by Repository">
+  ${_modeSelect}
+  <div class="filter-text-input">${_searchInput}</div>
+</div>`);
 ```
 
 ```js
 import * as Plot from "npm:@observablehq/plot";
 
 const _chartModeValue = _modeValue(_chartModeState);
-const _chartWsFiltered = _workstreamsForMode(_chartModeValue, wsAll);
+const _chartSearchValue = String(_chartSearchState ?? "");
+const _chartWsFiltered = _workstreamsForMode(_chartModeValue, wsAll)
+  .filter(w => workplanMatchesSearch(w, _chartSearchValue));
 
 // Sort by domain, then repository, then most recently updated workplan.
 // The axis labels show each domain/repo group once.
@@ -320,6 +352,10 @@ function _wsTitle(d) {
 
 // ── Render ────────────────────────────────────────────────────────────────────
 if (chartWs.length === 0) {
+  const _searchQ = _chartSearchValue.trim();
+  if (_searchQ) {
+    display(html`<p style="color:gray">No workplans match “${_searchQ}” for the selected mode.</p>`);
+  } else {
   const _emptyMsg = {
     proposed: "No proposed workplans.",
     ready: "No ready workplans.",
@@ -339,6 +375,7 @@ if (chartWs.length === 0) {
     month: "No workplans changed this month.",
   };
   display(html`<p style="color:gray">${_emptyMsg[_chartModeValue] ?? "No workplans."}</p>`);
+  }
 } else {
   display(Plot.plot({
     y: {
@@ -680,6 +717,7 @@ display(Inputs.table((summary.recent_progress ?? []).map(e => ({
 .live-indicator { font-size: 0.8rem; color: gray; position: relative; padding: 0.55rem 1.8rem 0.55rem 0.7rem; margin-bottom: 0.75rem; }
 .ws-mode-bar { margin-bottom: 0.75rem; }
 .ws-mode-select { min-width: 18rem; max-width: 100%; padding: 0.35rem 0.5rem; border-radius: 4px; border: 1px solid var(--theme-foreground-faint, #ddd); background: var(--theme-background); color: var(--theme-foreground); font: inherit; }
+.ws-search-input { min-width: 14rem; max-width: 100%; height: 30px; font-size: 0.85rem; padding: 0.25rem 0.5rem; border-radius: 6px; border: 1px solid var(--theme-foreground-faint, #ccc); background: var(--theme-background, #fff); font-family: inherit; color: inherit; }
 .card { background: var(--theme-background-alt); border-radius: 8px; padding: 1rem; }
 .card.warn { border: 2px solid orange; }
 .card-link { cursor: pointer; transition: box-shadow 0.15s, transform 0.1s; text-decoration: none; color: inherit; display: block; }
diff --git a/dashboard/test/workplan-search.test.mjs b/dashboard/test/workplan-search.test.mjs
new file mode 100644
index 0000000..33f5940
--- /dev/null
+++ b/dashboard/test/workplan-search.test.mjs
@@ -0,0 +1,42 @@
+import assert from "node:assert/strict";
+import test from "node:test";
+import {readFileSync} from "node:fs";
+import {dirname, join} from "node:path";
+import {fileURLToPath} from "node:url";
+
+import {workplanMatchesSearch} from "../src/components/workplan-search.js";
+
+const root = dirname(fileURLToPath(import.meta.url));
+const indexMd = readFileSync(join(root, "../src/index.md"), "utf-8");
+
+const sample = {
+  id: "abc-123",
+  title: "Overview Workstream Stage Counts",
+  repo_label: "state-hub",
+  domain: "infotech",
+  workplan_filename: "STATE-WP-0057-overview-workstream-stage-counts.md",
+  owner: "codex",
+};
+
+test("empty query matches all workplans", () => {
+  assert.equal(workplanMatchesSearch(sample, ""), true);
+  assert.equal(workplanMatchesSearch(sample, "   "), true);
+  assert.equal(workplanMatchesSearch(sample, null), true);
+});
+
+test("matches title, repo, domain, filename, owner, and id", () => {
+  assert.equal(workplanMatchesSearch(sample, "stage counts"), true);
+  assert.equal(workplanMatchesSearch(sample, "STATE-HUB"), true);
+  assert.equal(workplanMatchesSearch(sample, "Infotech"), true);
+  assert.equal(workplanMatchesSearch(sample, "wp-0057"), true);
+  assert.equal(workplanMatchesSearch(sample, "codex"), true);
+  assert.equal(workplanMatchesSearch(sample, "abc-123"), true);
+  assert.equal(workplanMatchesSearch(sample, "railiance"), false);
+});
+
+test("overview chart wires the text filter into Workplans by Repository", () => {
+  assert.match(indexMd, /workplanMatchesSearch/);
+  assert.match(indexMd, /ws-search-input/);
+  assert.match(indexMd, /Filter by title, repo, domain/);
+  assert.match(indexMd, /## Workplans by Repository/);
+});