diff --git a/services/intake/.clickhouse-version b/services/intake/.clickhouse-version
new file mode 100644
index 0000000000..59c8fb1977
--- /dev/null
+++ b/services/intake/.clickhouse-version
@@ -0,0 +1 @@
+26.3
diff --git a/services/intake/README.md b/services/intake/README.md
index fc02964f24..0306eba666 100644
--- a/services/intake/README.md
+++ b/services/intake/README.md
@@ -54,6 +54,9 @@ environment instead of package-scoped `uv run --package ...` commands.
 
 Prerequisite: Docker must be installed and running locally.
 
+Intake is tested and profiled on ClickHouse 26.3 LTS. Other ClickHouse versions
+may not be supported.
+
 Start a local ClickHouse container for span and trace storage:
 
 ```bash
diff --git a/services/intake/scripts/spans/run_clickhouse.sh b/services/intake/scripts/spans/run_clickhouse.sh
index 17829ca9a3..bced9e21cf 100755
--- a/services/intake/scripts/spans/run_clickhouse.sh
+++ b/services/intake/scripts/spans/run_clickhouse.sh
@@ -5,11 +5,12 @@
 set -euo pipefail
 
 container_name="nmp-intake-clickhouse"
-image="${CLICKHOUSE_IMAGE:-clickhouse/clickhouse-server:24.3}"
 clickhouse_user="${CLICKHOUSE_USER:-default}"
 clickhouse_password="${CLICKHOUSE_PASSWORD:-}"
 script_dir="$(cd -- "$(dirname -- "${BASH_SOURCE[0]}")" && pwd)"
 repo_root="$(cd -- "${script_dir}/../../../.." && pwd)"
+clickhouse_version="$(tr -d '[:space:]' < "${script_dir}/../../.clickhouse-version")"
+image="${CLICKHOUSE_IMAGE:-clickhouse/clickhouse-server:${clickhouse_version}}"
 data_dir="${CLICKHOUSE_DATA_DIR:-${repo_root}/tmp/intake-clickhouse}"
 
 ensure_host_dirs() {
@@ -21,13 +22,25 @@ ensure_tmp_dir() {
   docker exec "${container_name}" sh -c "mkdir -p /var/lib/clickhouse/tmp && chown clickhouse:clickhouse /var/lib/clickhouse/tmp" >/dev/null
 }
 
+ensure_expected_image() {
+  local actual_image
+  actual_image="$(docker inspect --format "{{.Config.Image}}" "${container_name}")"
+  if [[ "${actual_image}" != "${image}" ]]; then
+    echo "${container_name} uses ${actual_image}, but Intake requires ${image}." >&2
+    echo "Remove the existing container after preserving any data you need, then rerun this script." >&2
+    exit 1
+  fi
+}
+
 if docker ps --filter "name=^/${container_name}$" --filter "status=running" --format "{{.Names}}" | grep -qx "${container_name}"; then
+  ensure_expected_image
   ensure_tmp_dir
   echo "${container_name} is already running"
   exit 0
 fi
 
 if docker ps -a --filter "name=^/${container_name}$" --format "{{.Names}}" | grep -qx "${container_name}"; then
+  ensure_expected_image
   ensure_host_dirs
   docker start "${container_name}" >/dev/null
   ensure_tmp_dir
diff --git a/services/intake/src/nmp/intake/spans/evaluation_session_repository.py b/services/intake/src/nmp/intake/spans/evaluation_session_repository.py
index b809c82589..839072b031 100644
--- a/services/intake/src/nmp/intake/spans/evaluation_session_repository.py
+++ b/services/intake/src/nmp/intake/spans/evaluation_session_repository.py
@@ -171,7 +171,7 @@ async def list_sessions(
         if needs_pre_metrics:
             # Two-query path for cost/tokens sorts.
             #
-            # ClickHouse 24.3 inlines CTEs (does not materialise them), so a single query that
+            # ClickHouse inlines regular CTEs (does not materialise them), so a single query that
             # references `page_sessions` from multiple downstream CTEs (current_page_spans,
             # session_metrics, session_scores, final SELECT) would re-execute the expensive
             # all-session span aggregation once per reference. Splitting into two queries
@@ -340,7 +340,7 @@ def _metric_sort_page_ids_sql(
     ORDER BY + LIMIT/OFFSET to return the ordered (workspace, session_id) pairs for
     the requested page. Only IDs are returned — row hydration is a separate query.
 
-    Why separate: ClickHouse 24.3 inlines CTEs rather than materialising them, so a
+    Why separate: ClickHouse inlines regular CTEs rather than materialising them, so a
     single query that references `page_sessions` from multiple CTEs would re-execute
     the expensive all-session span aggregation once per reference. Returning IDs here
     and hydrating in _hydrate_by_ids_sql ensures the aggregation runs exactly once.
diff --git a/services/intake/tests/integration/spans/conftest.py b/services/intake/tests/integration/spans/conftest.py
index 65b1001783..88946c6061 100644
--- a/services/intake/tests/integration/spans/conftest.py
+++ b/services/intake/tests/integration/spans/conftest.py
@@ -9,6 +9,7 @@
 from collections.abc import Callable
 from datetime import datetime, timezone
 from importlib.util import find_spec
+from pathlib import Path
 from typing import Any
 from uuid import uuid4
 
@@ -23,6 +24,9 @@
 )
 from nmp.testing import create_test_client
 
+_CLICKHOUSE_VERSION_FILE = Path(__file__).resolve().parents[3] / ".clickhouse-version"
+CLICKHOUSE_VERSION = _CLICKHOUSE_VERSION_FILE.read_text(encoding="utf-8").strip()
+
 
 def _run(coro: Any) -> Any:
     return asyncio.run(coro)
@@ -55,7 +59,7 @@ def clickhouse_container():
     from testcontainers.clickhouse import ClickHouseContainer
 
     with ClickHouseContainer(
-        "clickhouse/clickhouse-server:24.3",
+        f"clickhouse/clickhouse-server:{CLICKHOUSE_VERSION}",
         username="test",
         password="test",
         dbname="default",
@@ -63,6 +67,11 @@ def clickhouse_container():
         yield container
 
 
+@pytest.fixture(scope="session")
+def clickhouse_version() -> str:
+    return CLICKHOUSE_VERSION
+
+
 @pytest.fixture(scope="session")
 def clickhouse_settings(clickhouse_container) -> ClickHouseSettings:
     return ClickHouseSettings(
diff --git a/services/intake/tests/integration/spans/test_clickhouse_bootstrap.py b/services/intake/tests/integration/spans/test_clickhouse_bootstrap.py
index db26401b5b..9d6149b60e 100644
--- a/services/intake/tests/integration/spans/test_clickhouse_bootstrap.py
+++ b/services/intake/tests/integration/spans/test_clickhouse_bootstrap.py
@@ -11,6 +11,17 @@
 from nmp.intake.spans.clickhouse_client import ClickHouseSpanClient, bootstrap_schema
 
 
+def test_clickhouse_server_matches_supported_lts(
+    clickhouse_client: ClickHouseSpanClient,
+    clickhouse_version: str,
+    run_async,
+) -> None:
+    result = run_async(clickhouse_client.query("SELECT version()"))
+
+    assert len(result.result_rows) == 1
+    assert str(result.result_rows[0][0]).startswith(f"{clickhouse_version}.")
+
+
 def test_clickhouse_bootstrap_is_idempotent(clickhouse_client: ClickHouseSpanClient, run_async):
     run_async(bootstrap_schema(clickhouse_client))
     run_async(bootstrap_schema(clickhouse_client))